Seitinrete, the Lost Vessel

Trample, protection from auras

Sorcery spells you cast have cipher. (After you cast that spell, you may exile it encoded on a creature you control. Whenever that creature deals combat damage
to a player, its controller may cast a copy of the encoded card without paying its mana
cost.)

Seitinrete, the Lost Vessel gets +2/+2 for each sorcery spell encoded on it.