Mr. Mime, Trap Terror

Bloodlust (whenver this creature kills a creature or deals combat damage to a player, put an experience counter on it)
Creatures you control get +X/+0 where X is the number of walls you control
{w}: Sacrifice a wall, prevent X damage to any target where X was the sacrificed wall's toughness
{u}: Remove all experience counters from this creature, create that many 0/2 Illusory Wall Creature Tokens