League of Legends blind baron steal

Ok I'm going to assume you know literally nothing about League. So the big purple thing the blue team is fighting is Baron Nashor. It has a ton of health, does a lot of damage to anything nearby, takes a fairly long time to take BUT it gives the team that kills it a huge buff that usually gives the team that takes it a huge boost to winning the match. Long story short, it's a big deal.

So TSM just won a fight leaving only Piglet alive, they go for baron, which by all rights is theirs for the taking at this point. The 'jungler' on their team, Santorin, has an ability called Smite, which at this point in the game does about 750 instant damage to any neutral monster, and means that when it gets low all he needs to do is use smite on the baron and they secure it.

Piglet is wandering around outside the pit, TSM has complete vision of him, while Piglet has no vision of what's happening inside the pit. He can't see the baron's health or how quickly it's dying or anything. He walks up, fires a completely blind shot into the pit, and manages to hit it RIGHT at the point where HE gets the killing blow on it, and takes it away from TSM. Even WITH vision on baron this would have been insane, the fact that he just went "About... now would do it" is unbelievable.

Disregarding the fact that Santorin is a pretty shit jungler and didn't even bother to use smite here...

I don't think Liquid, the team that stole it, had vision on the area so Piglet couldn't see how much health Baron had, so he just kinda threw his ability out there and got it. Baron gives the team that kills it a huge buff and that steal swung the momentum of the game