It’s actually even better than I thought, since the gem creation happens between exploding the gem and resolving the board, which means it’s more likely to create a 4/5 match since they’re filling a smaller space.
Immunity to stun is perfect in a Titan-rich environment, as well. I think it’s a great alternative to Forest Troll, which doesn’t require a lot of green gems to already be present - a game-changer, in other words 
.