Okay, explain this

[ElementalDearWatson]

I'm fighting a Gold deck and it's coming down to the wire.  It's my turn.  The AI has enough attack to kill me.  I have enough attack to kill the AI if I can buy one more turn.

The only thing I can do is use a Mindgate, which gets me a Purify.  I use it on myself, even though doing so won't secure me the win - the AI now has exactly the right amount of attack to get my HP down to zero, rather than getting me down to -2.

I play on anyway, and the first thing the AI does on its turn?  Plays its Purify on me.  Purify is applied on your opponent's turn before they attack, meaning that when the AI's round is over I have 2 HP, am not dead and get the win on my next turn.

What did it think it was doing?

[Solaris]

Artificial Imbecility at it's finest.

[Physsion]

The AI really liked the fact that you were using a Mindgate deck, and wanted to give you the win for it.

[CuCN]

If you had a weapon and it was frozen, it might be because of this bug.

[andretimpa]

AI doesn't know what to do with purify, so it followed your lead.

[ElementalDearWatson]

If you had a weapon and it was frozen, it might be because of this bug.

I don't think so, but I couldn't swear.  I don't remember having a weapon out, but it did hit me with an Ice Bolt the round before, so it's possible that I did and that it froze.