Medomai the Ageless and Mistmeadow Vanisher on the battlefield.
An opponent cannot block Medomai.
({1} magic symbol) ({U} magic symbol) the first turn available.
Steps
Cast Metamorphic Alteration by paying ({1} magic symbol) ({U} magic symbol) , attaching it to Medomai, naming Mistmeadow Vanisher and causing Medomai to become a copy of Mistmeadow Vanisher.
Declare Medomai as an attacker.
Medomai triggers, exiling Metamorphic Alteration until your end step.
When Metamorphic Alteration leaves the battlefield, Medomai is no longer a copy of Mistmeadow Vanisher.
Deal combat damage using Medomai.
Medomai triggers, causing you to take an extra turn after this one.
At the beginning of your end step, Medomai triggers, returning Metamorphic Alteration to the battlefield from exile attached it to Medomai, naming Mistmeadow Vanisher and causing Medomai to become a copy of Mistmeadow Vanisher.