Murda, Who Summons

Lifelink, partner (You can have two commanders if both have partner.)
While casting Murda, Who Summons or other commander spells you own, you may sacrifice a creature, discard a card, and pay 3 life rather than pay those card's commander tax.
Sacrifice Murda, Who Summons: Put a +1/+1 counter on each legendary creature you control.