 <p>Array index start from 0.<br> I presume when you say it hides the right answer button is when the answer is "2", since by your <code>giveHint</code> function it will remove index 1 from <code>answers</code> array which is "2".</p> <p>Change your <code>giveHint</code> removeAtIndex will do the trick.</p> <pre><code>func giveHint(sender: UIButton){ if self.answer != "1" { answers.removeAtIndex(0) Button1.alpha = 0 } else if self.answer != "2" { answers.removeAtIndex(1) Button2.alpha = 0 } else if self.answer != "3" { answers.removeAtIndex(2) Button3.alpha = 0 } else if self.answer != "4" { answers.removeAtIndex(3) Button4.alpha = 0 } } </code></pre>