You control a Warrior that does not have summoning sickness and that cannot be blocked and killed by an opponent.
Steps
Declare a Warrior you control as an attacker, triggering
Najeela, creating a 1/1 Warrior creature token that is tapped and attacking.
When the Warrior enters the battlefield,
Intruder Alarm triggers, untapping all creatures.
Holding priority, activate
Jegantha by tapping it, adding ({W} magic symbol) ({U} magic symbol) ({B} magic symbol) ({R} magic symbol) ({G} magic symbol) that cannot be spent to pay generic mana costs.
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.