Sovereigns of Lost Alara + Colossification

Prerequisites

Your commander can attack this turn. An opponent is unable to block your commander.

Steps

1. Declare your commander as an attacker, attacking an opponent unable to block it.
2. Sovereigns of Lost Alara's exalted and second abilities trigger.
3. Resolve Sovereigns of Lost Alara's exalted trigger, giving your commander +1/+1 until end of turn.
4. Resolve Sovereigns of Lost Alara's second ability, searching your library for Colossification, putting it onto the battlefield attached to your commander, and shuffling your library.
5. Deal combat damage with your commander.
6. The opponent that was dealt damage loses the game due to being dealt at least twenty-one combat damage by your commander.