Summary Prospectus by Investment Company (Form 497K)

SUMMARY PROSPECTUS

July 10, 2026

Horizon Defensive Core Fund

Advisor Class: HESAX

Institutional Class: HESIX

Investor Class: HESGX

Before you invest, you may want to review the Prospectus for the Defensive Core Fund (as defined below), which contains more information about the Defensive Core Fund and its risks. The current statutory Prospectus and Statement of Additional Information ("SAI") dated July 10, 2026, are incorporated by reference into this Summary Prospectus. You can find the Defensive Core Fund's Prospectus, SAI, reports to shareholders, and other information about the Defensive Core Fund online at www.horizonmutualfunds.com/defc-fund.html. You can also get this information at no cost by calling 1-855-754-7932 or by sending an e-mail request to [email protected].

Investment Objective

The investment objective of the Horizon Defensive Core Fund (the "Defensive Core Fund" or the "Fund") is to seek to capture the majority of returns associated with U.S. equity market investments, while mitigating downside risk through the use of a risk overlay strategy (the "Risk Assist^® strategy").

Fees and Expenses of the Defensive Core Fund

This table describes the fees and expenses that you may pay if you buy, hold and sell shares of the Defensive Core Fund. You may pay other fees, such as brokerage commissions and other fees to financial intermediaries, which are not reflected in the tables and examples below.

Annual Fund Operating Expenses (expenses that you pay each year as a percentage of the value of your investment)	Advisor Class	Institutional Class	Investor Class
Management Fees	0.68%	0.68%	0.68%
Distribution and/or Service (12b-1) Fees	0.25%	None	0.10%
Other Expenses(1)	0.14%	0.14%	0.14%
Acquired Fund Fees and Expenses(2)	0.01%	0.01%	0.01%
Total Annual Fund Operating Expenses(3)	1.08%	0.83%	0.93%

(1)	"Other Expenses" are estimated for the current fiscal year for the Institutional Class.

(2)

Acquired Fund Fees and Expenses are the indirect costs of investing in other investment companies. The operating expenses in this fee table will not correlate to the expense ratio in the Fund's financial highlights because the financial statements include only the direct operating expenses incurred by the Fund.

(3)

Note that the Total Annual Fund Operating Expenses shown in the table above differ from the ratio of expenses to average net assets included in the Defensive Core Fund's financial highlights section of the Prospectus. The financial highlights reflect operating expenses and include expense reductions from securities lending but exclude indirect expenses.

Example: This Example is intended to help you compare the cost of investing in the Defensive Core Fund with the cost of investing in other mutual funds. The Example assumes that you invest $10,000 in the Defensive Core Fund for the time periods indicated and then redeem all of your shares at the end of those periods. The Example also assumes that your investment has a 5% return each year and that the Defensive Core Fund's operating expenses remain the same. Although your actual costs may be higher or lower, based upon these assumptions your costs would be:

	1 Year	3 Years	5 Years	10 Years
Advisor Class	$110	$343	$595	$1,317
Institutional Class	$85	$265	$460	$1,025
Investor Class	$95	$296	$515	$1,143

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Portfolio Turnover. The Defensive Core Fund pays transaction costs, such as commissions, when it buys and sells securities (or "turns over" its portfolio). A higher portfolio turnover rate may indicate higher transaction costs and may result in higher taxes when Fund shares are held in a taxable account. These costs, which are not reflected in annual fund operating expenses or in the Example, affect the Defensive Core Fund's performance. During the most recent fiscal year ended November 30, 2025, the Defensive Core Fund's portfolio turnover rate was 216% of the average value of the portfolio.

Principal Investment Strategies of the Defensive Core Fund

The Defensive Core Fund seeks to achieve its investment objective by utilizing two strategies: (1) the Core Equity Strategy; and (2) the Risk Assist^® Strategy. The Core Equity Strategy invests primarily in common stocks of large and mid-cap U.S. companies that exhibit high quality and growth characteristics, while the Risk Assist^® Strategy is an actively managed risk reduction strategy intended to guard against large declines in the Fund's equity portfolio. The Fund's investment adviser (Horizon Investments, LLC ("Horizon" or the "Adviser")) will determine how to allocate the Defensive Core Fund's assets between the Core Equity Strategy and the Risk Assist^® Strategy.

Core Equity Strategy. Horizon executes the Core Equity Strategy by investing the Fund's assets primarily in equity securities of large and mid-cap U.S. companies. Horizon generally considers large and mid-cap companies to be those that are within the range of the S&P 500 and S&P 400 indices when purchased. However, the Fund can invest in companies of any size, which may include small-cap companies, at the discretion of Horizon.

Horizon employs a multi-factor process to select investments that Horizon believes have high quality and growth characteristics as compared to the market generally. Horizon considers high quality characteristics to include, without limitation, high profitability and stable earnings; low price variability; low fundamental valuation measures; and high recent price trends. Horizon considers growth characteristics to include, without limitation, revenue growth, earnings per share (EPS) growth, gross profit, and free cash flow (FCF) growth.

Horizon selects and weights securities using a flexible approach that combines active management and quantitative models to allocate the Fund's portfolio between issuers, sectors and/or factors (e.g., growth, profitability, sentiment and fundamental safety) that Horizon believes offer the opportunity for the highest quality characteristics that may provide higher projected return for a given amount of risk. In constructing the portfolio, Horizon may consider industry and position constraints to ensure sufficient diversification, as determined by Horizon, and may invest in other investment companies, including ETFs, that invest in equity securities of U.S. companies. The Core Equity Strategy expects securities with the foregoing characteristics in aggregate to have a similar performance and risk as traditional U.S. equity markets. In addition, the Defensive Core Fund may buy or write options on puts or calls for investment purposes, to hedge other investments or to generate option premiums for the Fund and may implement such investments through option combinations such as spreads, straddles, and collars.

The Defensive Core Fund's option strategies may involve options combinations, such as straddles, spreads or collars. In "straddles," the Defensive Core Fund purchases a put option and a call option or writes a put option and a call option on the same instrument with the same expiration date and the same strike price. In "spread" transactions, the Fund buys and writes a put or buys and writes a call on the same underlying instrument with the options having different exercise prices, expiration dates, or both. When the Defensive Core Fund engages in spread transactions, it seeks to profit from differences in the option premiums paid and received and in the market prices of the related options positions when they are closed out or sold. A "collar" position combines a put option purchased by the Fund (the right of the Fund to sell a specific security within a specified period) with a call option that is written by the Fund (the right of the counterparty to buy the same security) in a single instrument, and the Fund's right to sell the security is typically set at a price that is below the counterparty's right to buy the security. Thus, the combined position "collars" the performance of the underlying security, providing protection from depreciation below the price specified in the put option, and allowing for participation in any appreciation up to the price specified by the call option. In each case, the premium received for writing an option offsets, in part, the premium paid to purchase the corresponding option; however, downside protection may be limited as compared to just owning a single option. There is no limit on the number or size of the options transactions in which the Defensive Core Fund may engage; however, the Fund will not use options for the purpose of increasing the Defensive Core Fund's leverage with respect to any portfolio investment. The Fund's options strategy is primarily intended to enhance the defensive characteristics of the Fund, principally through the use of put options, put spreads, or similar option strategies designed to provide additional downside

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protection for the Fund's equity portfolio. Secondarily, the Fund may use call options or call spreads to provide the opportunity for capital appreciation from time to time. The Defensive Core Fund does not anticipate writing options on individual securities that it does not hold in its portfolio (i.e., "naked" options).

The Fund expects to engage in frequent buying and selling of securities to achieve its investment objective.

Risk Assist^®Strategy. Under the Risk Assist^® strategy, Horizon continually measures market conditions with a specific focus on characteristics that indicate abnormal or severe risk conditions (such as increases in market volatility and decreases in global equity markets), in order to apply a proprietary process that prompts a risk reduction of the portfolio. The Defensive Core Fund typically executes this strategy by investing up to 100% of the Defensive Core Fund's portfolio in U.S. Treasuries or other cash equivalents, which may include, without limitation, U.S. Treasury-focused securities, which may include, without limitation, Treasury bonds, Treasury notes, Treasury Inflated Protection Securities (collectively, "U.S. Treasury Securities"); exchange traded options on U.S. Treasury Securities; repurchase agreements fully collateralized by U.S. Treasury Securities; and money market instruments, including obligations of U.S. and foreign banks, corporate obligations, U.S. government securities, municipal securities, repurchase agreements and asset-backed securities, paying a fixed, variable or floating interest rate (collectively, "Cash Equivalents"); or money market funds or ETFs that invest in Cash Equivalents (collectively "Defensive Investments"). The Defensive Core Fund may invest in U.S. Treasury Securities without regard to maturity or duration.

Although Horizon may elect to allocate 100% of the Defensive Core Fund's assets to the Risk Assist^® strategy, it is not required to. Instead, Horizon typically employs the Risk Assist^® strategy in stages, and Horizon may elect to allocate between 0% and 100% of the Defensive Core Fund's assets to the Risk Assist^® strategy, depending on Horizon's determination of current market risk.

The Risk Assist^® algorithm includes a process by which it systematically attempts to protect investment gains within the portfolio based on Horizon's measures of perceived risk. The result of this process is referred to as a "ratchet". To implement the ratchet, Horizon first determines the lowest portfolio value that the algorithm is calculated to accommodate during any 12-month period. As the Risk Assist^® strategy portfolio value grows (typically when the portfolio has experienced 3-5% of appreciation, depending on market conditions), the Risk Assist^® algorithm will increase (i.e., "ratchet" up) the value of the loss tolerance limit in an attempt to protect those gains.

There can be no guarantee that the Risk Assist^® strategy, including the ratchet function, will be successful in preventing losses in the Fund's portfolio, and investors may lose money by investing in the Fund.

Principal Risks of the Defensive Core Fund

Many factors affect the Defensive Core Fund's performance. The Defensive Core Fund's share price changes daily based on changes in market conditions in response to economic, political and financial developments. The direction and extent of those price changes will be affected by the financial condition, industry and economic sector of the securities in which the Defensive Core Fund invests. The Defensive Core Fund is not federally insured or guaranteed by any government agency. You may lose money by investing in the Defensive Core Fund.

Risk Assist^® Strategy Risk. The ability of the Defensive Core Fund to meet its investment objective is directly related to Horizon's ability to effectively allocate Fund assets to, and otherwise implement, the Risk Assist^® strategy. Implementing the Defensive Core Fund's Risk Assist^® strategy may result in periods of time when the Defensive Core Fund is invested primarily (or entirely) in Cash Equivalents (as opposed to equity securities). There can be no guarantee that the Risk Assist^® strategy, including the ratchet function, will be successful in preventing losses in the Defensive Core Fund's portfolio. Because the Risk Assist^® strategy may be implemented in stages, the Defensive Core Fund may have market exposure during times when the Risk Assist^® strategy is being implemented. To the extent that the Risk Assist^® strategy is implemented, the Defensive Core Fund will likely not benefit from capital appreciation or income from the equity markets. To the extent that the Risk Assist^® strategy is not implemented in a timely manner, the Defensive Core Fund may underperform. The Defensive Core Fund's portfolio managers analysis of economic trends, or other matters could be wrong and may not produce desired results.

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Management Risk. The ability of the Defensive Core Fund to meet its investment objective is directly related to the allocation of the Defensive Core Fund's assets. Horizon may allocate the Defensive Core Fund's investments so as to under-emphasize or over-emphasize investments at the wrong times or under the wrong market conditions, in which case the Defensive Core Fund's value may be adversely affected.

Market Risk. Investments in securities in general are subject to market risks that may cause their prices to fluctuate over time. The Fund's investments may decline in value due to factors affecting securities markets generally, or particular countries, segments, economic sectors, industries or companies within those markets. The value of a security may decline due to general economic and market conditions that are not specifically related to a particular issuer. Markets may, in response to governmental actions or intervention, economic or market developments, trade disputes, the spread of infectious illness or other public health issues, geopolitical factors or other external factors, experience periods of high volatility and reduced liquidity, and, in extreme cases, may lead to trading restrictions and halts. These and other similar events could be prolonged and could adversely affect the value and liquidity of the Fund's investments and negatively impact the Fund's performance.

Operational and Technology Risk. Cyber-attacks, disruptions, or failures that affect the Defensive Core Fund's service providers or counterparties, issuers of securities held by the Defensive Core Fund, or other market participants may adversely affect the Defensive Core Fund and its shareholders, including by causing losses for the Defensive Core Fund or impairing its operations.

Quantitative Model Risk. The Risk Assist^® strategy relies heavily on quantitative models and the analysis of specific metrics to construct and implement the Risk Assist^® strategy portion of the Defensive Core Fund. The impact of these metrics on performance can be difficult to predict. In addition, relying on quantitative models entails the risk that the models themselves may be limited or incorrect, that the data on which the models rely may be incorrect or incomplete, and that Horizon may not be successful in determining the weighting of particular investments in the Defensive Core Fund's portfolio. Any of these factors could cause the Defensive Core Fund to underperform funds with similar strategies that do not utilize quantitative analysis.

Frequent Trading and Turnover Risk. The Fund may engage in frequent trading to achieve its investment objectives. As a result of its trading strategies, the Fund may sell portfolio securities without regard to the length of time they have been held and will likely have a higher portfolio turnover rate than other mutual funds. Since portfolio turnover may involve paying brokerage commissions and other transaction costs, higher turnover generally results in additional expenses, which may lower the performance of the Fund, and may also result in the realization of short-term capital gains. The Fund must generally distribute realized capital gains to shareholders, increasing the Fund's taxable distributions. High rates of portfolio turnover in a given year would likely result in short-term capital gains, which are taxed to shareholders at ordinary income tax rates.

Domestic Strategy Risk. Because the Defensive Core Fund will invest primarily in securities of U.S. issuers, the Defensive Core Fund is subject to the risk that certain changes in the U.S. economy, such as when the U.S. economy weakens or when its financial markets decline, may have an adverse effect on the securities to which the Defensive Core Fund has exposure, and the Defensive Core Fund will be restricted in its ability to allocate its investments to the securities of non-U.S. issuers.

Equity Securities Risk. Equity securities typically have greater price volatility than fixed-income securities. The market price of equity securities owned by the Defensive Core Fund may go down, sometimes rapidly or unpredictably. Equity securities may decline in value due to factors affecting equity securities markets generally, particular industries represented by those markets, or factors directly related to a specific company, such as decisions made by its management.

Fixed-Income Risk. The Defensive Core Fund will be subject to fixed-income risks to the extent that the Defensive Core Fund implements the Risk Assist^® strategy. The value of investments in fixed-income securities, options on fixed-income securities and securities in which the underlying investments are fixed-income securities, are expected to fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of the fixed-income securities owned by the Defensive Core Fund or its underlying investments. Issuers of floating rate debt are exposed to higher interest payments in a rising rate environment. Issuers may default on interest and principal payments. Generally, securities with lower debt ratings ("junk bonds") have greater credit risk.

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Interest Rate Risk. When the Defensive Core Fund invests in bonds (either directly or through underlying investments), the value of your investment in the Defensive Core Fund will fluctuate with changes in interest rates. Typically, a rise in interest rates causes a decline in the value of bond funds owned by Defensive Core Fund or its underlying investments. In general, the market price of debt securities with longer maturities will increase or decrease more in response to changes in interest rates than shorter-term securities.

Sector and Focus Risk. To the extent that the Defensive Core Fund focuses its investments in particular asset classes or sectors of the economy, any market price movements, regulatory or technological changes, or economic conditions affecting companies in those asset classes or sectors may have a significant impact on the Defensive Core Fund's performance.

Smaller and Medium Issuer Risk. Small and medium capitalization companies may be more vulnerable than larger, more established organizations to adverse business or economic developments. In addition, small and medium capitalization companies may be particularly affected by interest rate increases, as they may find it more difficult to borrow money to continue or expand operations, or may have difficulty in repaying any loans.

Large Capitalization Company Risk. Large capitalization companies as a group could fall out of favor with the market, causing the Defensive Core Fund to underperform investments that focus on small or mid-cap companies.

U.S. Government Securities Risk. The Fund's investment in U.S. government obligations may include securities issued or guaranteed as to principal and interest by the U.S. government, or its agencies or instrumentalities. Payment of principal and interest on U.S. government obligations may be backed by the full faith and credit of the United States or may be backed solely by the issuing or guaranteeing agency or instrumentality itself. There can be no assurance that the U.S. government would provide financial support to its agencies or instrumentalities (including government-sponsored enterprises) where it is not obligated to do so. In addition, U.S. government securities are not guaranteed against price movements due to changing interest rates.

Money Market Fund Risk. An investment in a money market fund is not a bank deposit and is not insured or guaranteed by any bank or any government agency. It is possible for the Defensive Core Fund to lose money by investing in money market funds. The value of money market instruments may be affected by changing interest rates and by changes in the credit ratings of the investments held by the money market fund.

Investments in Other Investment Companies Risk. The Fund may invest in the securities of other investment companies, such as mutual funds, closed-end funds, business development companies, and ETFs. These investments expose the Fund to the risks of the underlying funds, including the risk that those funds may not achieve their investment objectives or may underperform. The Fund will also bear its proportionate share of fees and expenses of the underlying funds, which may increase overall costs. Regulatory limits may restrict the Fund's ability to invest in other funds.

Fluctuation of Net Asset Value ("NAV"); Unit Premiums and Discounts. The NAV of the shares of the ETFs in which the Multi-Factor U.S. Equity Fund may invest will generally fluctuate with changes in the market value of the ETF's securities holdings and supply and demand of the ETF's shares on the exchanges on which the ETF's shares are traded. The market prices of an ETF's shares may deviate significantly from the NAV of the ETF's shares during periods of market volatility or reduced liquidity. If the Multi-Factor U.S. Equity Fund purchases an ETF's shares at a time when the market price is at a premium to the NAV of the ETF's shares or sells at a time when the market price is at a discount to the NAV of the ETF's shares, then the Multi-Factor U.S. Equity Fund may sustain losses that are in addition to any losses caused by a decrease in NAV.

Options Risk. Investments in options involve risks different from, or possibly greater than, the risks associated with investing directly in securities, including leverage risk, tracking risk and, in the case of over-the-counter options, counterparty default risk. Option positions may expire worthless exposing the Defensive Core Fund to potentially significant losses. If the Defensive Core Fund writes options, it may receive a premium that is small relative to the loss realized in the event of adverse changes in the value of the underlying instruments. When the Defensive Core Fund utilizes options spreads, collars or other combinations, the premium received for writing the call option offsets, in part, the premium paid to purchase the corresponding put option; however, the Defensive Core Fund's participation in gains above the price of the call option are forfeited in return for receiving the call option premium. While the Fund's options strategy is primarily intended to enhance the Fund's defensive characteristics, there can be no assurance that

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the options strategy will achieve its intended results, and the use of options may, in certain market conditions, result in losses that are greater than would have been incurred in the absence of such options positions. The Fund's use of options strategies, including straddles, may be subject to special federal income tax rules that may, among other things, affect the character of gains and losses realized by the Fund, accelerate recognition of income to the Fund, and defer the Fund's ability to recognize losses. These rules could therefore affect the character, amount, and timing of distributions to shareholders.

Performance

The bar chart illustrates the risks of investing in Investor Class shares of the Defensive Core Fund by showing the Defensive Core Fund's average returns for each calendar year since inception. The Average Annual Total Returns table shows how the Defensive Core Fund's average annual returns compare with those of a broad measure of market performance. The Defensive Core Fund's past performance, before and after taxes, is not necessarily an indication of how the Defensive Core Fund will perform in the future. Updated performance information is available at no cost by visiting www.horizonmutualfunds.com or by calling 1-855-754-7932.

Calendar Year Return as of December 31
Investor Class

During the period shown in the bar chart, the best performance for a quarter was 13.69% (for the quarter ended December 31, 2020). The worst performance was -13.95% (for the quarter ended June 30, 2022).

Defensive Core Fund
Average Annual Total Returns

For the periods ended December 31, 2025	One Year	Five Years	Since Inception of Class*
Investor Class
Return Before Taxes	9.48%	11.35%	12.94%
Return After Taxes on Distributions	5.78%	10.33%	11.89%
Return After Taxes on Distributions and Sale of Fund Shares	8.29%	8.95%	10.30%
Advisor Class
Return Before Taxes	9.33%	11.18%	12.78%
S&P 500 Total Return Index (reflects no deduction for fees, expenses or taxes)	17.88%	14.42%	14.99%

*	Investor Class shares commenced operations on December 26, 2019. Advisor Class shares commenced operations on January 8, 2020. Institutional Class shares had not commenced operations prior to the date of this Prospectus. Index information is since inception of Investor Class shares.

After-tax returns are based on the highest historical individual U.S. federal marginal income tax rates, and do not reflect the impact of state and local taxes; actual after-tax returns depend on an individual investor's tax situation and may differ from those shown. If you own shares of the Defensive Core Fund in a tax-deferred account, such as an

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individual retirement account ("IRA") or a 401(k) plan, after-tax returns are not applicable to your investment. After-tax returns are shown for Investor Class shares only and after-tax returns for other classes will vary to the extent that each class has different expenses.

The S&P 500 Total Return Index is an unmanaged market capitalization-weighted index which is comprised of the largest U.S. domiciled companies and includes the reinvestment of all dividends. Investors cannot directly invest in an index.

Returns would have been lower if Horizon had not waived and/or reimbursed certain expenses of the Defensive Core Fund during the periods shown.

Investment Adviser. Horizon Investments, LLC serves as the investment adviser to the Defensive Core Fund.

Portfolio Managers. Scott Ladner, Chief Investment Officer of Horizon, Mike Dickson, Ph.D., Head of Research and Quantitative Strategies of Horizon, and Clark Allen, Director of Quantitative Research, share responsibility for the day-to-day management of the Defensive Core Fund as Co-Portfolio Managers. Mr. Ladner and Dr. Dickson have each been a Co-Portfolio Manager of the Defensive Core Fund since its inception in December 2019 and Mr. Allen has been a Co-Portfolio Manager since March 2023.

Purchase and Sale of Fund Shares. You may purchase and redeem shares of the Defensive Core Fund on any day that the New York Stock Exchange is open for trading, subject to certain restrictions described under the section titled "How to Purchase Shares" and "How to Redeem Shares" of the Defensive Core Fund's Prospectus. Purchases and redemptions may be made by mailing an application or redemption request to Horizon Funds c/o U.S. Bank Global Fund Services, PO Box 219252, Kansas City, MO 64121-9252, or by calling 1-855-754-7932. You also may purchase and redeem shares through a financial intermediary. The minimum initial investment in the Defensive Core Fund is $2,500 and the minimum subsequent investment is $250 for Advisor Class and Investor Class shares. The minimum initial investment in the Defensive Core Fund is $10 million for Institutional Class shares. There is no minimum subsequent investment for Institutional Class shares.

Tax Information. The Defensive Core Fund's distributions are taxed as ordinary income or capital gains, unless you are investing through a tax- deferred arrangement, such as a 401(k) plan or an individual retirement account. Such tax-deferred arrangements may be taxed later upon withdrawal of monies from those arrangements.

Payments to Broker-Dealers and Other Financial Intermediaries. If you purchase the Defensive Core Fund through a broker-dealer or other financial intermediary (such as a bank), the Defensive Core Fund and its related companies may pay the intermediary for the sale of Fund shares and related services. These payments may create a conflict of interest by influencing the broker-dealer or other intermediary and your salesperson to recommend the Defensive Core Fund over another investment. Ask your salesperson or visit your financial intermediary's website for more information.

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