Your team finishes of baron, a bit early, and your all low on HP, you all head to the same bush to recall and a Teemo shroom is there,PENTA.

You are playing Teemo, but you are dead. Your allied Darius is chasing the enemies who are all still at full health. Miraculously, they hit every single shroom you planted. Penta.

Entire enemy team dies to a single Karthus Q.

Your karthus Qs but everyone of them has a tiny bit of HP left, Soraka just happens to be surrounded and uses Star Call. Penta.

The enemy is all in the same lane single file, Draven Qs, Lux Qs, then Ezreal Qs one right after another. Penta

Ok, this is really complicated and you're going to die a lot of times trying to pull it off. It'll prolly go away once riot changes the items. But what you do is play GP, and buy a wriggles. Then buy 5 tiamats. Then laugh hilariously at how 20% of the time that you can get the entire enemy team really centrally located to a minion, you can parrrley the minion and watch it proc the 425, but splash to the champions for 175% dmg. Which equals you doing around 750 splash dmg to everyone in the blast radius.

Basically you can ks your entire team with one shot.

1: Be Swain
2. Transform
3. Flash in the teamfight at the last moment
4. ???
5. Profit

Orianna pull all enemys to the exact same spot and bring them down to 1 hp. Then Trundle use his E and they all die. (Trunde E do 1 true damage to get turret aggro)

CAWCAWCAWCAWCAWCAWCAWCAWCAWCAWCAWCAWCAWCAWCAWCAWCA WCAWCAWCAW!!!!!!!!!!!!!!!!!! Penta.

1: Katarina
2: Group
3: Penta

Malzahar is farming his malefic visions on some minions when he gets ganked by the entire enemy team. However, his team is nearby and a teamfight starts. Malzahar's whole team dies, but all 5 of the enemy and Malzahar are extremely low and are all running away...just then, Malzahar's malefic visions transfer from the last minion to a nearby enemy champion, and kills all 5 of them