He's really good at racking up the % but doesn't really have any 'guaranteed' kill setups like some other characters, his kill moves are his Smashes naturally (Dsmash isn't as reliable as the other two), down B, and all his aerials.
Best to 'worst' for each category goes in this order:
Smashes: Usmash/Fsmash are both equally as good imo, then Dsmash.
Aerials: Uair, Nair, Fair, then Dair.
Usmash: Covers a lot of range above him and for an Usmash its range in front of him is great too.
Fsmash: He rears back before lunging forward and striking so it's like a dodge-and-hit, which naturally catches people out. Great reach on this. *Be careful to not use it up too close or you can utterly miss with this and be left wide open.
Dsmash: Has weaker parts of its hitbox where it won't kill, and even the stronger parts of it aren't always reliable, gotta have 'em at higher %'s and close to the ledge. Still not a bad move imo.
DownB: If you catch them with the first hit of the grounded version of this it usually (but not always) links into the 2nd hit which kills. As a side note, this move does ridiculous shield damage and breaks shields a ton, which obviously leaves them open for you to act on.
Uair: Comes out really fast, great range. Probably his most reliable aerial kill move.
Nair: This move also comes out really fast. It doesn't knock them out as far as a smash, but it's initial knockback is enough to get the kill if you're close enough to the side of the stage without any real trouble. You can use the late-hitbox on it to easily gimp people offstage and stop them from recovering as well.
Fair: As you know this move spikes, but it can also hit them to the sides depending on where you hit with it.
Bair: The first hit drags them down and it takes a bit before they can act, so it's good for gimping if you can land only that single hit. The last hit kills surprisingly reliably at higher %'s, gotta be careful about the end lag on this one if you miss though.
Dair: Ok this one's really situational, but the last hit of Dair pops your opponent up. On high %'s it either does this or sends them to the sides, which also kills. Not reliable, but it's worth knowing anyway. It's very hard to land the last hit on grounded opponents too unless they're above you on a platform, otherwise you want to hit them with this when they're in mid-air.
Jab 1 and eggs set up for most of these moves by the way, just gotta be careful about them shielding it.