[Set] RestTalk + Curse

 

This Gigalith has an advantage over the others : it can heal itself. With Curse, it will raise its Attack and Defense stats and can become hard to knock out. That will make it loose Speed, but that's not a very big problem as Gigalith is already very slow. When you feel the need to heal, use Rest. Sleep Talk is here to not stay inactive during the two turns of sleep, it will be able to set up or attack with Stone Edge. However, this set can be a bit hard to set up because of Gigalith's weaknesses, its counters should be knocked out before. Also, you can't control what your Gigalith will do when you use Sleep Talk. In the worst cases, it could use Rest although it's already sleeping, which will make it fail and you will basically loose a turn ! And, be wary of Stone Edge's low PP, when they run out, Gigalith won't have any way to do damage.

Variants

-Use a more offensive EV spread.

-Replace Curse with Earthquake.

-Use another item, for example a Lum Berry to skip the sleep turns the first time Rest is used.