Sun and Moon have been a boon to Trick Room, breathing a new life into it this generation, and Marowak-A is one of the strongest Trick Room users this gen, with incredibly low speed, and a base attack stat of 80, backed by Thick Club, standing at a whopping 568 attack with zero setup. 568 still not enough for you? He's got access to Sword's Dance for your setup leisure. And at 45 base speed, gettin' all the way down to an 85 total speed stat, Marowak-A's gonna be using that beastly attack first a lot.
Marowak-A likes to throw around recoil-less Flare Blitzes like nobody's business, and his other STAB in Shadow Bone is great, whacking those Psychics who hit Fidgit super-effectively, and knocking those Ghosts that can spin-block Fidgit for a loop, as well as having a 20% chance to lower the defense of whatever he doesn't kill. His Fire STAB covers Fidgit's Ice weakness, and Fidgit can spin away those pesky Stealth Rocks that make Marowak-A's life a Never-Ending Nightmare. (Get it?? ;D) You think you can come in with a Fire-type and resist his STAB? Have fun watching him smack down your Fire-types by throwing his dead mama's thigh at 'em, or making the ground tremble and lurch beneath their feet. Even the Flying-types who are immune to his Ground attacks, such as Cawmodore and Tomohawk, he can just smash 'em in the face with a Flare Blitz.
All in all, with Marowak-A's blistering speed inside Fidgit's Trick Room, and his great Attack, doubled by a Thick Club and backed by powerful, recoil-less STAB, makes him an excellent abuser and defender of Fidgit's setup. And y'know the best part? He's not walled by Skarmory! :D gg, you flying fortress!
Some numbers:
252+ Atk Thick Club Marowak-Alola Flare Blitz vs. 252 HP / 252+ Def Skarmory: 354-416 (105.9 - 124.5%) -- guaranteed OHKO
252+ Atk Thick Club Marowak-Alola Earthquake vs. 252 HP / 252+ Def Heatran: 476-564 (123.3 - 146.1%) -- guaranteed OHKO
252+ SpA Heatran Earth Power vs. 248 HP / 0 SpD Marowak-Alola: 260-306 (80.4 - 94.7%) -- guaranteed 2HKO
252+ Atk Heatran Earthquake vs. 248 HP / 8 Def Marowak-Alola: 170-202 (52.6 - 62.5%) -- guaranteed 2HKO
If Heatran is holding an Air Balloon, Marowak-A will always break its balloon with Shadow Bone, survive an Earth Power or Earthquake (barring a crit or Specs or Band), and KO back with Earthquake.
252+ Atk Thick Club Marowak-Alola Flare Blitz vs. 4 HP / 0 Def Cawmodore: 494-584 (204.1 - 241.3%) -- guaranteed OHKO
252+ SpA Tomohawk Earth Power vs. 248 HP / 0 SpD Marowak-Alola: 238-282 (73.6 - 87.3%) -- guaranteed 2HKO
252+ Atk Thick Club Marowak-Alola Flare Blitz vs. 252 HP / 252 Def Tomohawk: 262-310 (63.2 - 74.8%) -- guaranteed 2HKO
Marowak-A will survive Tomo's Earth Power, and since Nature Power turns into Tri-Attack, a normal type move, in a lack of Terrain, Tomohawk will have no priority attack to hit Marowak-A, giving Marowak-A the second move he needs to score the KO.
0 SpA Slowbro-Mega Scald vs. 248 HP / 0 SpD Marowak-Alola: 260-308 (80.4 - 95.3%) -- guaranteed 2HKO
252+ Atk Thick Club Marowak-Alola Shadow Bone vs. 252 HP / 80+ Def Slowbro-Mega: 228-270 (57.8 - 68.5%) -- guaranteed 2HKO
Again barring a crit, Marowak-A will win if he gets the switch-in attack against Mega Slowbro.
252+ Atk Gliscor Earthquake vs. 248 HP / 8 Def Marowak-Alola: 266-314 (82.3 - 97.2%) -- guaranteed 2HKO
252+ Atk Thick Club Marowak-Alola Flare Blitz vs. 252 HP / 252 Def Gliscor: 211-249 (59.6 - 70.3%) -- guaranteed 2HKO after Poison Heal
Even in this very unlikely situation against Gliscor, Marowak-A still survives one hit by a super-effective Earthquake, and 2HKOs back with a faster Flare Blitz.
252+ Atk Thick Club Marowak-Alola Shadow Bone vs. 252 HP / 252+ Def Tapu Lele: 380-450 (110.4 - 130.8%) -- guaranteed OHKO
Just 'cause I hate Lele.
Wouldya look at all that damage? Even against mons stacked against him, Marowak-A comes with no Z-Moves or setup necessary, just fast, powerful attacks breaking through everything in sight. You scared of Trick Room yet?
"Come now, CAPer, now is not the time for fear. That comes later."
- Alolan Marowak