Here is how Primus gets killed in War of the Apocalypse.
Emerl: Let's hurry up!
Tino Tonitini: Got it!
(They try to get away but a missile came out of nowhere and blast the two heroes)
Primus: I will not let you escape!
Emerl & Tino: Primus!
Leonardo: You better step aside!
(He fires Missiles but they dodge)
Emerl: Go! I'll take care of him!
(Emerl and Primus came face to face)
Primus: I've been waiting for decades!
Emerl: Not going to happen! You cannot defeat me, so you must give up!
Primus: I'LL NEVER LET YOU LIVE WHEN I WANT ALL OF YOU DIE!!! AND WE WILL STILL USE LEGENDARY POKEMON AS WEAPONS!!!!!
(They begin to fight each other)
Flain: Keep Fighting!
Krader: You can do this!
Telso: Defeat, Primus!
(Emerl and Primus continues fighting)
Primus: Give up!
Emerl: Never! I can't let you have all Legendary Pokémon! Ever!
(Emerl kicks Primus but he blocks the kicks grabs Emerl in the neck and throws him into the building)
Primus: I see you are getting so weak. Besides, I should be more stronger.
Emerl: I can't give up!
(Emerl tries to get up but Primus kicks him and then chokes him)
Primus: You will be finished, Emerl!
Emerl: (Choking) Get off me!
Primus: (Laughing Evilly) You are a fool! I told you can't defeat me!
(She tries to save him but Primus kicks her away)
Xion: He's too strong!
(Primus toss Emerl away hard and crashes into the ground)
(Zekrom and Kyurem fight. Zekrom fires Dragon Pulse but Kyurem dodge the attack, then Zekrom turns to see Primus and Emerl)
Primus: Now it's time I end you! ONCE! AND! FOR! ALL!!!!!
Primus: What was that? Oh no!
(Zekrom activates Fusion bolt and hits Primus)
(Zekrom's fusion bolt kills Primus as everyone looks at the event)
Emerl: Primus is gone.
Krader: Zekrom destroy Primus!
(Zekrom then looks at everyone)
Emerl: Thank you.
(Zekrom then leaves to continue the Legendary Pokémon war)
Emerl: Ugh... ow..
Xion: Emerl, are you okay?
Emerl: I'm fine. But we have to continue our final battle.