Gigalith @ Rockium Z / Hard Stone
Ability: Sand Stream
EVs: 252 HP / 252 Atk / 4 SpD
Brave Nature
IVs: 0 Spe
- Rock Slide
- Stone Edge / Curse
- Heavy Slam
- Protect / Wide Guard

TR sweeper - can hit the spdef benchmark listed below if willing to give up some attack

Gigalith @ Rockium Z / Leftovers / Figy Berry
Ability: Sand Stream
EVs: 252 HP / 80 Atk / 40 Def / 136 SpD
Brave Nature
IVs: 0 Spe
- Rock Slide
- Heavy Slam
- Curse
- Protect

curse set
252 SpA Life Orb Sheer Force Landorus Earth Power vs. 252 HP / 136 SpD Gigalith in Sand: 312-369 (83.4 - 98.6%) -- guaranteed 2HKO
252+ Atk Guts Hariyama Close Combat vs. +1 252 HP / 40 Def Gigalith: 314-372 (83.9 - 99.4%) -- guaranteed 2HKO
rest in attack