Gatecrash

Flying Battalion — Whenever this creature and at least two other creatures attack, this creature deals 3 damage to any target and you gain 3 life.

Hexproof Whenever a creature card is put into an opponent's graveyard from anywhere, you may have Lazav become a copy of that card, except its name is Lazav, Dimir Mastermind, it's legendary in addition to its other types, and it has hexproof and this ability.

(T: Add R or W.) As this land enters, you may pay 2 life. If you don't, it enters tapped.

(T: Add R or G.) As this land enters, you may pay 2 life. If you don't, it enters tapped.

Double strike Bloodrush — 3RR, Discard this card: Target attacking creature gets +3/+3 and gains double strike until end of turn.