No, the effect is not just "if your opponent uses hasten". If your opponent draws two or more cards, period. So yes, FGs get hosed by this, but yet, it remains balanced against players, because players can choose to draw cards or not.
???
So you want a card that is instant-win against ALL False Gods?
After you played this (non-destructible) card, no creature of the False God would attack for the
rest of the match and there would be NO counter to it!
This "draw two or more cards" is
called hasten in Elements, so I don't see any reason not to use it.
As for the situational situation, think about it: it goes only one way. So while your opponent can only draw one card a turn (otherwise forgoes his attack), you can draw as much as you like. So it's massive card advantage or tempo advantage for you.
???
What? You do realize that "you can draw as much as you like" even
without this card, right?
Brain Freeze would basically counter
ONE card in this game, Hourglass. You don't think a card whose sole purpose is to counter
ONE other card, is
maybe a little bit too situational?
1. If your opponent doesn't have Hourglass -> Brain Freeze is 100% useless
2. If your opponent has Hourglass, but you draw Brain Freeze later in the game -> Brain Freeze is 95% useless (because opponent probably stopped drawing multiple cards anyways so that he won't deck out)
3. If your opponent has Hourglass and you draw Brain Freeze early in the game -> ...
Does it damage your opponent? No.
Does it heal you? No.
Then what does it do?
..It stalls the game
IF your opponent draws multiple cards.