Najeela, the Blade-Blossom | Bear Umbra

Cards

Bear Umbra attached to
Najeela.
Najeela does not have summoning sickness.
An opponent is unable to kill
Najeela.
Lands you control can tap to produce at least ({W} magic symbol) ({U} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) .

Declare
Najeela as an attacker, attacking an opponent unable to block and kill it.
Najeela and
Bear Umbra triggers.
Resolve the
Najeela trigger, creating a 1/1 Warrior creature token that is tapped and attacking.
Resolve the
Bear Umbra trigger, untapping all lands you control.
Activate all lands you control by tapping them, adding ({W} magic symbol) ({U} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) .
Activate
Najeela by paying ({W} magic symbol) ({U} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) , untapping all attacking creatures, giving them trample, lifelink and haste, and gaining an additional combat phase after this one.
Repeat each combat phase.