Najeela, the Blade-Blossom

Whenever a Warrior attacks, you may have
its controller create a 1/1 white Warrior
creatures 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 this
ability only during combat.