Okay. Gliscor with Poison Heal, Toxic Orb, and Facade. Is it a good idea?
Toxic Orb + Poison Heal has been a notoriously strong strategy ever since Breloom gained it in Generation 4 and Gliscor soon followed next generation. It heals more than Leftovers, can't be stopped by Knock Off unless Gliscor loses it switching in, and comes with the added boon of status immunity.
However, Facade isn't great on Gliscor and you're better off abusing STAB Earthquake. You might want to use moves like Toxic and Knock Off to cripple would-be walls, and using Roost to increase your own longevity.
Looking at the comments, this seems to be for doubles. Landorus-T is significantly better there due to being able to secure many OHKOs or 2HKOs along with a much stronger Earthquake. Gliscor's health recovery is insignificant in doubles and Gliscor itself is much weaker offensively.