Medomai the Ageless | Satoru Umezawa

Cards

You control an additional nontoken creature that does not have summoning sickness.
An opponent is unable to block creatures you control.

({4} magic symbol) ({U} magic symbol) ({U} magic symbol) ({B} magic symbol) ({B} magic symbol) each turn available.

Declare the additional creature as an attacker, attacking an opponent unable to block it.
When the creature is unblocked, activate
Medomai's ninjitsu ability by paying ({2} magic symbol) ({U} magic symbol) ({B} magic symbol) and returning the creature to your hand, putting
Medomai onto the battlefield tapped and attacking.
Deal combat damage with
Medomai, triggering its ability, causing you to take an extra turn after this one.
Before the combat phase ends, activate the creature card in your hand's ninjutsu ability by paying ({2} magic symbol) ({U} magic symbol) ({B} magic symbol) and returning
Medomai from the battlefield to your hand, putting the creature onto the battlefield tapped and attacking.
Repeat each turn.