<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>0024 - Disclosure - 18. Subsequent Events</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>2</Level><ElementName>us-gaap_SubsequentEventsTextBlock</ElementName><ElementPrefix>us-gaap_</ElementPrefix><IsBaseElement>true</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="From2011-07-01to2012-06-30" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;Common stock&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In July 2012, the Company issued an aggregate of 1,200,000
shares of common stock at $0.20, per share, for legal services.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In July and August 2012, the Company converted an aggregate
of 40 shares of Series A Preferred stock to 526,253 shares of common stock at a conversion rate of $.10, per share, including accrued
dividends, penalty and interest.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In October 2012, the Company converted 100 preferred shares
of stock to 2,780,602 shares of common stock at a conversion rate of $0.05, per share, including accrued dividends, penalty and
interest, pursuant to an agreement with the investor.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In October 2012, the Company sold an aggregate of 300,000
shares of the Company&amp;#146;s common stock and a warrant to purchase 249 shares of Class B common stock of RBMS to three investors
of the Company for $30,000.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;On October 15, 2012, the Company issued 300,000 shares of
common stock at $0.20, per share, for legal services pursuant to an agreement dated April 23, 2012.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In October, 2012, the Company issued an aggregate of 62,253
shares of common stock at $0.30, per share, to the investment banker in connection with financings.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;On November 8, 2012, the Company issued 100,000 shares of
common stock at $0.15, per share, in settlement of accounts payable.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In December 2012, the Company issued an aggregate of 1,400,000
shares of common stock, at $0.20, per share, for compensation to employees valued at $280,000.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In December 2012, the Company issued 20,000 shares of common
stock at $0.20, per share for consulting services.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In January 2013, the Company issued 1,200,000 shares of common
stock at $0.20, per share for legal services.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In February 2013, the Company the Company converted 50 shares
of Series A Preferred stock to 723,534 shares of common stock at a conversion rate of $.10, per share, including accrued dividends,
penalty and interest.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In March 2013, the Company issued 50,000 shares of common
stock at $0.20, per share, for repayment of loans on behalf of RBMS.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In May 2013, the Company issued 2,000,000 shares of common
stock at $0.20, per share, as loan collateral.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In June 2013, the Company issued 92,400 shares of common stock
@ $0.20, per share, for fees to the investment banker.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In June 2013, the Company issued 50,000 shares of common stock
@ $0.20, per share for repayment of loan on behalf of RBMS.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In June 2013, the Company issued an aggregate of 1,280,000
shares of stock and a warrant to purchase 1,280,000 shares of common stock as compensation to officers and affiliates of the Company.&amp;#160;&amp;#160;The
warrant is exercisable at $0.20, per share, for 5 years.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In July 2013, the Company issued 164,671 shares common stock
@ $0.10, per share for repayment of note payable and accrued interest.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;In July 2013, the Company issued a warrant to purchase 100,000
shares of common stock exercisable at $0.15, per share for 5 years.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;On September 6, 2012, the Company issued a promissory note
in the amount of $80,000, with 185,000 shares of common stock as interest. Pursuant to the terms of the note, if the promissory
note is not repaid by May 20, 2013 the Company is to use its best efforts to liquidate shares of its common stock to repay the
loan.&amp;#160;&amp;#160;As of July 15, 2013, no payments have been made on the promissory note.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;On January 14, 2013 the Company entered into a non-exclusive
agreement with an investment banker, financial advisor and consultant for a term of six months.&amp;#160;&amp;#160;The investment banker
is entitled to a cash placement fee of 8% of the total purchase price of the Company&amp;#146;s securities sold, adjusted by the exercise
of any investor warrants, in connection with a placement resulting from the investment banker&amp;#146;s introduction.&amp;#160;&amp;#160;In
addition, the banker shall receive a placement fee equal to 4% of the total purchase price of the Company&amp;#146;s securities sold
and a warrant to purchase common shares of the Company equal to 8% of the funds raised, as defined. If the investment banker introduces
the Company during the term to a transaction which becomes a merger, acquisition, joint venture or similar transaction, the Company
shall pay the banker a fee in combination of stock and cash that reflects the exact percentage of stock and or cash used for the
transaction, as defined.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;On June 10, 2013, the Company agreed to sell up to an aggregate
of $250,000 in convertible promissory notes under a securities purchase agreement (Agreement) with an aggregate stated value equal
to the purchaser&amp;#146;s subscription amount and a warrant to purchase up to a number of shares of common stock equal to 100% of
the purchaser&amp;#146;s subscription amount divided by $0.15 with an exercise price of $0.15 exercisable immediately with a term
of five years.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;On June 10, 2013, under the Agreement,
the Company issued a two-year, 10% convertible promissory note in the amount of $20,000 to an investor.&amp;#160;&amp;#160;121 days from
the issue date, the holder can convert any unpaid principal and accrued interest into common shares of the Company. Between 121
days and 210 days from the issue date, the conversion price per share shall be $0.15; after 210 days from the issue date, the conversion
price shall be $0.10; subject to adjustment as defined. . The investor also was issued a five year common stock purchase warrant
for the purchase of up to 133,334 shares of the Company&amp;#146;s common stock, at a price per share of $0.15, that permits a cashless
exercise in the event that the underlying shares of common stock to be issued upon exercise are not registered pursuant to an effective
registration statement at the time of the exercise.&amp;#160;&amp;#160; In addition, if while the warrant is outstanding, the Company effects
a merger or consolidation, sells all of its assets or enters into other specifically defined transactions, the warrant will be
exercisable into shares of the surviving entity as defined.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;On July 2, 2013, under the Agreement, the Company issued four
two-year, 10% convertible promissory notes in the amount of $10,000 each.&amp;#160;&amp;#160;The investors also were issued a five year
common stock purchase warrant for the purchase of up to 67,000 shares of the Company&amp;#146;s common stock, at a price per share
of $0.15, that permits a cashless exercise in the event that the underlying shares of common stock to be issued upon exercise are
not registered pursuant to an effective registration statement at the time of the exercise.&amp;#160;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0"&gt;On July 2, 2013 the Company issued a five year warrant to
purchase of up to 100,000 shares of the Company&amp;#146;s common stock, at a price per share of $0.15, to the investment banker in
payment for commissions due.&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

&lt;p style="font: 8pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in"&gt;&amp;#160;&lt;/p&gt;

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