I want to see an ability on a future hero that is like this:

Duel
A target enemy unit becomes locked into a Duel with you.. Neither you, nor them can be damaged, healed or receive any buffs of any sort from an outside source other than whom you are in a duel with.. Until one of you kill the other or until 2000 range is exceeded... breaking the duel.

Poppy's Ult

There would be a lot of balancing if that's used, especially if the ability holder is a solid DPSer.

That said, the next best (or at least most similar) is Poppy's ultimate, Diplomatic Immunity.

Let's call it Diplomatic Immunity instead. Oh, wait...

Screw Diplomatic Immunity, make this a summoner spell >

As people have said, it's be over powered on a pure DPS class at the very least (though it isn't mentioned what type it should go on). Considering all you'd have to do is pop it on like their healer, and they're screwed.

Both people would have to accept it.

Problem solved.

Yeah, but then it'd be almost pointless. Not only would it take a few seconds to hit yes or no to distract them, they'd only hit yes if they knew they could beat you obviously. Why take a risk on a 1v1 when your whole team is fighting?

I want to see a summoner spell called 'Rant' where a HUUUUUUUUGE speech bubble comes out from your character and nobody can see a **** thing for a few seconds.