Magni, Icon of Strength

As long as creatures you control have a combined power of 12 or less, Magni, Icon of Strength isn't a creature.
Whenever Magni, Icon of Strength becomes blocked it gains trample, indestructible and +X/+0 until end of turn, where X is its toughness. Whenever Magni, Icon of Strength blocks a creature it gains first strike, indestructible and +