And that, is why I still can't aprove this card.
This is the reason i don't like this card too.
Play some basilisk blood when the player have only 1 creature on the field and BAM: 20 HP and an instakill.
I know it's a 2 cards combo, but it's really easy to play and it gives you 2 dinstinct effects: 20 damage (very powerful) and an instakill (OP, currently only Shockwave + Congeal can achieve it).
It's far more powerful than Unstable Gas, since you damage your opponent and eliminate an offense.
At least Unstable Gas stays vulnerable for 1 turn.