Lumen-Class Frigate

Station (Tap another creature you control: Put charge counters equal to its power on this Spacecraft. Station only as a sorcery. It's an artifact creature at 12+.)
2+ | Other creatures you control get +1/+1.
12+ | Flying, lifelink

Unstoppable Slasher

Deathtouch
Whenever this creature deals combat damage to a player, they lose half their life, rounded up.
When this creature dies, if it had no counters on it, return it to the battlefield tapped under its owner's control with two stun counters on it.

Strategic Betrayal

Target opponent exiles a creature they control and their graveyard.

Mardu Siegebreaker

Deathtouch, haste
When this creature enters, exile up to one other target creature you control until this creature leaves the battlefield.
Whenever this creature attacks, for each opponent, create a tapped token that's a copy of the exiled card attacking that opponent. At the beginning of your next end step, sacrifice those tokens.