I'd add Mega Glalie to Spikes users, it might seem a little bit odd to dedicate your Mega Pokemon to a Spikes user, but i really feel like it's worth it with Glalie. Glalie should be getting plenty of opportunities to set up some layers of Spikes by forcing switches considering just how hard it hits and how good Ice is as an offensive typing, and thanks once again to that excellent STAB, pretty much every common Defog user in the tier absolutely hates being matched up against the thing. Gligar, Golbat, and Shiftry get hit super effectively by Return/Ice Shard, and Skuntank, while neutral to Ice, still takes an insane amount from Return. This makes Glalie exceptionally good at defending its entry hazards, since not a single Defog user can remove them 1v1, and even if they do manage to find an opportunity to clear the entry hazards away, they simply grant Glalie a free switch in to either immediately reset them or punish them severely for doing so with its powerful STAB moves.
Last but not least, it's pretty notable that Glalie is an offensive Spikes Setter that has uses outside of just setting Spikes. You really have to admit, while Omastar, Accelgor, and suicide lead Qwilfish are pretty good at getting entry hazards up, but they really don't do much outside of that imo (bulky Qwilfish averts this since Intimidate and its defensive typing let it check a few things, and it fits significantly more easily on offensive teams than Roselia does) Glalie is an exception to this, doubling as a threatening offensive Pokemon instead of simply setting Spikes, which gives it a bit more flexibility in how it can be used throughout the game imo.
