Gate Colossus
Artifact Creature — Construct
This spell costs 
less to cast for each Gate you control.
Gate Colossus can't be blocked by creatures with power 2 or less.
Whenever a Gate enters the battlefield under your control, you may put Gate Colossus from your graveyard on top of your library.
8/8
Illustrated by
Ravnica Allegiance Promos#232UncommonEnglishLegality
Rulings
Jan 25, 2019
Once a creature with power 3 or greater has blocked this creature, changing the power of the blocking creature won’t cause this creature to become unblocked.