Are you saying it does 2 damage to all creatures, or only those burrowed?
I'm saying it would do two things, in order.
1. Find and unburrow all burrowed creatures on the board.
2. Deal 2 damage to all/enemy creatures (including the recently unburrowed creatures).
The idea is that this card would be a way to unburrow creatures (Pests, Graboids) then deal damage to them while dealing damage to multiple creatures at the same time.
And yep, no damage to immaterial creatures.