Imagine Gambit but instead of Gambit, it was League of Legends. Two teams on the same map and they have to defeat the other team's envoys/prime evil. You can have 3 lanes. The "towers" would just be really beefy envoys. The "Nexxus" would be a prime evil. Ads can still drop motes that you use to spawn ammo or power-ups(like 10 seconds of faster super charge rate for 15 motes or fast melee grenade... for 5 motes) I'd probably spend all my time in Gambit at that point. And you could increase it to 6v6 cause bigger maps.