I noticed there isn't a thread for underrated (/ creative) sets yet, so I'll just post it here. Rotom-W is in my opinion easily a top 10 mon in the tier at the moment. It consistently runs into favorable matchups as popular archetypes like bulky offense generally don't have great Wisp switchins and can't afford giving away too much momentum to Voltturn spam. The standard PDef set with Protect is the best fit for most teams, but I think there are two other amazing sets.
Rotom-Wash @ Leftovers
Ability: Levitate
Tera Type: Steel
EVs: 248 HP / 248 Def / 12 Spe
Bold Nature
IVs: 0 Atk
- Hydro Pump
- Volt Switch
- Will-O-Wisp
-
Thunder Wave
This is just the standard PDef set but with Thunder Wave over Protect. Protect is obviously great to get extra Leftovers recovery, get additional burn chip and to simply scout the opponent's sets, but I find it not as useful on teams without Great Tusk. Rotom-W is usually the early game pivot into opposing Great Tusk if you don't have a Great Tusk yourself, so in a lot of matchups you won't be playing with Leftovers. Protect is still a useful move from time to time but definitely less impactful without lefties recovery. Thunder Wave is a great alternative to cripple special attackers that are used to soak up the Will-o-Wisp like Iron Valiant and Dragapult and it's great as a last resort against set up sweepers like Volcarona, Espathra, and CM Valiant, although it's often necessary to use your Tera Steel. There are a few other minor advantages such as dealing with Tera 50/50s against the likes of Tera Fire Kingambit.
Rotom-Wash @ Leftovers
Ability: Levitate
Tera Type: Ghost
EVs: 252 SpA / 4 SpD / 252 Spe
Timid Nature
IVs: 0 Atk
- Hydro Pump
- Discharge
- Substitute
- Nasty Plot
Balance and bulky offense often resort to awkward pivotting to play around Wisp and Volt Switch and this set takes full advantage of that. Pokemon like Toxapex turn from a great switchin to standard PDef Rotom-W into setup fodder for SubNP Rotom-W. With the combination of Subsitute, Levitate, and Tera Ghost it also has a great 1v1 matchup against all Garganacl sets (Curse boosted Salt Cure breaks the Sub but Garg can't take a boosted Hydro Pump). I've tried playing around with a set of Nasty Plot, Thunder Wave, and Hex with Tera Ghost but it's very inconsistent and requires quite a lot of support. It's a fun set to use on mid ladder but I wouldn't recommend it personally.