Slowking-Galar @ Black Sludge
EVs: 252 HP / 136 Def / 120 SpD
IVs: 0 Atk
- Sludge Bomb
- Slack Off
- Ice Beam
This Mixed Defense Slowking-Galar utilizes the combination of Trick and Black Sludge to help wear down Steel-types like Corviknight, Ferrothorn, and Heatran, while using said mixed defensive investment to act as a reliable scout and check for lots of threats. Having Black Sludge also makes you an unfun target to Trick for things like Tapu Fini (although Sticky Barb Clefable is still unfun), which is nice. Sludge Bomb and Ice Beam are the best coverage options, letting you hit things for big damage that would force out the AV set (Weavile and Lando-T/Garchomp respectively).
The heavy physical defense investment lets this Slowking-Galar set tank unboosted HDB Weavile's Knock Off (71-84%), as well as Banded Weavile's Triple Axel (66-78%). Sludge Bomb back does 42-50%, and Weavile doesn't like being poisoned, so at the very least you aren't set up fodder for SD Weavile and aren't automatically forced out even at full. Scarf Kart's Knock Off has a shot to OHKO the standard AV Slowking-Galar after SR, but this set easily avoids that (mind you, you're still 2HKO'd so watch out). Offensive Lando-T and Garchomp can't OHKO from full with EQ (which they do to the standard AV Slowking-Galar), while Ice Beam OHKO's offensive Lando-T and has a 30% shot to do so to offensive Garchomp. Of course SpDef Lando-T is more common, but Ice Beam is still a clean 2HKO. Specs Lele has a 30% shot to OHKO the standard AV Slowking-Galar set with Psyshock after SR, but this set easily avoids that (in exchange for taking exactly the same from Psychic, i.e. 61-71%).
On the special side, this set is still pretty bulky, even though it isn't packing an AV or max SpDef investment. This set is still good for pivoting into strong special attackers and then swapping out to a better answer. The given EVs let Slowking-Galar avoid the OHKO from Specs Dragapult's Shadow Ball even after SR, and if SR aren't up, two max roll Specs Draco Meteors ain't doing the job ever from full either. Modest Nidoking's Earth Power has a less than 10% chance to OHKO with Earth Power, while Ice Beam is a clean 2HKO. You still handily check/counter things like offensive Torn-T (+2 Hurricane does 67-79%), Tapu Koko
Generally, use Trick early and often to start chipping down the aforementioned Steel-types, especially because said Steel-types are often a very good switch-in to Slowking-Galar's other sets. Also, you'll still want a way to pressure Steel-types more directly - stuff like Specs Lele, Magnezone, and Dragapult are all solid options, as they really appreciate the chip damage on opposing Steel-types that comes from a Tricked Black Sludge.