Pain Hammer Trevenant - Otter
CC Machine that just won't die
Build Path

Branch PokeFirst Pick
Damage. Slow.

Wood Hammer
AOE Damage. Displacement. Stun. Second activation: AOE Damage. Stun. Self-damage.

Pain Split
Reflects damage (Assassinate). HP Vamp and DOT at lesser HP. Swift.

Phantom ForestUNITE
AOE damage. Displacement. Slow. Shield (per opponent hit). Increases self-healing. Increases ally basic attacks to affected opponents.
Razor Claw
After using a move, the Pokémon's next basic attack deals more damage. If held by a melee Pokémon, the basic attack also slows opposing Pokémon.
Stat Boosts
Shield (Upon Unite)
Guide
My first guide so I apologize for any mistakes. May update with more info as I play more games with it.
The usual Trevenant build is Curse + Horn Leech, which got me thinking about how I can put its other under-utilized moves to good use too. Works nice with teams that have low damage, or bursty ones that appreciate well-timed stuns more.
I pick Branch Poke at the beginning usually because in the early game, will-o-wisp burn has a tendency to steal kills from your lane partner.
Use Wood Hammer to get surprise picks on enemies for your attacker. Wood Hammer synergizes really well with Razor Claw, since it procs on both hits. You can do a cool combo with Hammer > AA > Branch/Pain Split > AA > Hammer again > AA. This slows the enemy down for ages and they will often burn items like eject button to get away from it. Ideally you space the moves out in such a way that your attacker can get attacks in on the slowed enemies before you hit them with the next stunning move.
Pain Split keeps you alive, and makes you an infuriating decoy that's hard for opponents to get rid of. Whenever you're low, use this move on enemies pursuing you. They will often overextend MASSIVELY thinking only one more hit will kill you, over and over again. When you get too low, pop your potion and allow the combined healing of Focus Band + Natural Cure to Heal you back up like crazy.
In teamfights, the first thing you want to do is link yourself with PS to a close-range Pokemon so that they won't leave your range. Run around CCing people with Wood Hammer and the slows with Razor Claw. Always keep watch for enemies grouping up to fish for opportunities to use Phantom Forest. Since it gives Trevenant a colossal shield and cripples opponents, it's the best chance to suddenly melt them away by converging on them as a team.
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