Surging School

When Surging School enters the battlefield, sacrifice all non human blue creatures you control. Surging School gains {x} +1/+1 counters where {x} is the total strength of every creature sacrificed this way.
If Surging School would be dealt damage, prevent that damage and remove 2 +1/+1 counters from it, then create a 1/1 blue sea serpent creature token.