Optimus Prime, Hero

three generic mana one blue mana one red mana one white mana Legendary Artifact Creature — Robot·4/8

More Than Meets the Eye two generic mana

(You may cast this card converted for two generic mana

.)
At the beginning of each end step, bolster 1. (Choose a creature with the least toughness among creatures you control and put a +1/+1 counter on it.)
When Optimus Prime dies, return it to the battlefield converted under its owner's control.

Optimus Prime, Autobot Leader

Legendary Artifact — Vehicle·6/8

Living metal (During your turn, this Vehicle is also a creature.)
Trample
Whenever you attack, bolster 2. The chosen creature gains trample until end of turn. When that creature deals combat damage to a player this turn, convert Optimus Prime.