I take it Other cards would affect this too?
In theory, yes, but since it only works against creatures played from the hand no Other card actually affects this yet.
I don't realy like it. This creature could easily grow into huge proportions for only so litle quanta.
That's only if you don't deal with the problem early on with CC, Shields, etc... or outrush it with damage - while the effect is potent on a rainbow or duo, it basically requires the opponent to sit there and do nothing, when more elements usually means a bigger variety of options to deal with Aqua Shifter in the first place.
it reminds me a bit of pariah/exile, but more potent against duos.
Yeah, both cards do have an anti-rainbow intent in their effect, but as you noted Aqua Shifter plays better against duos in addition to gaining it's stat boost in a different way than Pariah does and having different counter strategies.
