I mean, there was no way the recaplet of the finale wasn’t going to start with a holy **** so let’s get that out of the way: HOLY SHIT.
Let’s also get this out of the way: mea culpa to everyone who called that Walter really did poison Brock. Even though it wasn’t exactly like y’all thought, and even though I certainly never maintained that it was something Walt wouldn’t do. The bastard.
Anyway, so what happened: in the aftermath of the car non-bomb, Jesse gets picked up by the Feds for questioning about his ricin claim re: Brock. This keeps him out of the way while Walt bull-in-a-china-shops his way to find Saul. He needs to find another venue where he can get to Gus, and after talking to Jesse, Saul gives Walt one possibility: Tio Salamanca. After ascertaining that Tio and Gus are enemies, Walt pays the old man a visit and gives him an opportunity for revenge.
The plan goes like this: Tio makes a request to see the DEA. Hank schleps in for the occasion only to get some slowly spelled out epithets tossed his way by Tio, but the point is that Gus hears about it. Tio’s gotta go. So while Walt hides out in at the old folks’ home, Gus sends Tyrus to scout Tio’s room and make sure the coast is clear for Gus to show up and give the old bastard a lethal injection. Only Tio gets the last laugh, as he rings his little bell that’s been rigged up to Walt’s bomb. Tio’s room goes BOOM, and Gus emerges … with the entire right side of his head blown off. Rest in peace, sweet chicken man.