The Hoenn Event will run for two weeks from Jan 15 until Jan 29. There are a bunch of things going on, and one of them is a new charge move. if you evolve Shroomish into Breloom during the event, it will have Grass Knot as it's charge move.
Gyms and Raids
Grass Knot will create the best move set for Breloom, neutral damage, no type effectivness. Compared with all other Pokemon, it is ranked #24 in DO@20, so it probably won't find many uses as a generalist. As a grass type, Breloom will be #4 behind Roserade and both Exeggutors in DO@20. It has the highest DPS of any grass type, but it's lower HP/TDO holds it back just a little. In this case, Breloom is #1 in DO@15. So against weaker Pokemon Breloom looks better, and against stronger Pokemon Roserade looks better. But instead of looking at grass types, I find it more useful look at the opponent's types. In this case, Grass is effective against ground, rock, and water.
As a specialist, Breloom looks quite useful. Against Ground types, Breloom is ranked #4 in DO@20. It is just above the new Feraligatr with Hydro Cannon. Ahead of it are Kyogre, Roserade and Weavile. Against Rock types, Breloom is ranked #2 in DO@20. Only Metagross (Bullet Punch + Meteor Mash) is ahead of it. Against Water types, Breloom is ranked #6 in DO@20. Electivire, Raikou, Luxray, Zapdos, Roserade are all ahead of it. But each are legendary, or require sinnoh stones. Breloom is very accessible compared to those guys.
Trainer Battles
It's very important to look at PvP seperately from Gyms and Raids. First, the moves themselves have different values. Also, survivability wins in PvP which means looking for highest TDO and not DO@20. In this case, Grass Knot is tied with Dynamic Punch for highest DPS movesets for Breloom.
In master league battles, it doesn't look useful because Brelook is ranked #94 overall in TDO. (This link shows Dynamic Punch, but remember it is tied with Grass Knot.) Against Ground types, Rock types, and Water types, Breloom + Grass Knot is ranked #33, #22, and #21 respectively. There are plenty of better options here.
Ultra Leagle battles tell a similar story. It is ranked #65 overall in TDO (This link shows Dynamic Punch, but remember it is tied with Grass Knot.) Against Ground types, Rock types, and Water types, Breloom + Grass Knot is ranked #31, #16, and #13 respectively. These are all higher than master league battles, but still not high enough to be useful in my opinion.
Great League battles tells the worst story. It is ranked #156 overall in TDO (This link shows Dynamic Punch, but remember it is tied with Grass Knot.) Against Ground types, Rock types, and Water types, Breloom + Grass Knot is ranked #51, #28, and #29 respectively.
The Silph Road Boulder Cup requires more details analysis. Since the boulder cup limits the types of Pokemon to only Rock, Ground, Steel and Fighting, Breloom might be useful here.
Comments or Suggestions
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