While people are bringing Arceus and Ursaluna to the Chesnaught raids, personally I prefer the mons that have to push the limits of their performance, and that's why I'm welcoming Chesnaught back with an Azurill solo to bring it full circle and show that even the mon with the 3rd lowest BST in the game can win just as well as any other mon when it comes to this raid event.
My Azurill set is very similar to my Marill set but with some slight differences. Like Marill, Azurill runs Eviolite with max Def/SpA EVs and the remainder in HP. Sap Sipper was bred from my Azumarill but Azurill doesn't have the same grass weakness so it's less vulnerable when abilities are disabled. The main difference is that I went for the natural Fairy tera and Draining Kiss over Rain Dance instead of running the same water tera + Rain Dance multiplier stacking. I went this harder route because Azurill would take a longer time to KO Chesnaught either way without the natural Water STAB boost, and Draining Kiss provided a consistent source of strong healing that prevented random crits from ending the run.
Compared to Marill, Azurill has the same 20 in both offenses but is less bulky and slower overall. Even with 20 base speed, my uninvested Azurill ended up outspeeding Chesnaught after -4 speed drops. Chesnaught still seems to open up with Wood Hammer either way so Azurill can get at least a Charm in early on and that's usually enough to get going.
The scariest threat Chesnaught has is a crit Stone Edge, but Azurill has room to survive it and make a comeback with Draining Kiss in return. Terastallization puts Draining Kiss up to 60BP, and the super STAB boost lets it heal fairly well through the shield and 75% healing allows it to almost fully heal even when coming from the red.
-6 0 Atk Tera Rock Chesnaught Stone Edge vs. 4 HP / 252 Def Eviolite Azurill on a critical hit: 153-180 (63.2 - 74.3%) -- guaranteed 2HKO
252+ SpA Tera Fairy Azurill Draining Kiss (60 BP) vs. -6 0 HP / 0 SpD Tera Rock Chesnaught: 284-336 (2.5 - 3% of 35x hp boss) -- possibly the worst move ever
Azurill's performance was consistent enough, but the success of the solo actually came down to the AI's contributions. On my first run I had an entirely physical team and ran out of PP by the end. On my second run I had both Clodsire and Dudunsparce wasting most of their time spamming their status moves against the shield and I ran out of time instead. The third and successful run featured Haxorus, Corviknight, and most importantly Arcanine who was one of the most important supporters with Leer, Intimidate, and a burn through shield early on that helped to lessen the death threshold of Stone Edge.
252+ SpA Tera Fairy Azurill Surf vs. -6 0 HP / 0 SpD Tera Rock Chesnaught: 426-502 (3.8 - 4.5% of 35x hp boss) -- possibly the worst move ever
My general game plan was to get all Charms and Fake Tears off and then just chip away at Chesnaught's HP. Against the shield, Draining Kiss does more damage after the 0.3x/0.7x non-matching/matching tera multipliers, but it also takes more ingame time to play the HP drain messages and the tera animation, so generally I tried to spam Surf. I used 2 attack boost cheers on the shield phase and saved one for afterwards since I felt like the multiplier would add the most damage after the shield, but also the shield phase felt like it was taking the most effort to break through. I had used some PP Ups after the first attempt, but in this run I didn't even need them since the base PP of each move was enough for the kill, which goes to show the variance that AI can have on runs when their damage output is actually relatively helpful.
Goodbye Chesnaught.
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