Zixza, the exiled Titan

Whenever a Warrior attacks, you may have its controller create a 1/1 white Warrior
creature token that's tapped and attacking.
{w}{u}{b}{r}{g}: Untap all attacking creatures.
They gain trample, lifelink, and haste until end
of turn. After this phase, there is an
additional combat phase.
Activate only during combat.