>>21397350Nope.
Of course it won't end up OU but there's no chance it will stay NU. 100 Speed isn't exactly bad in lower tiers. Its Return hits harder than Life Orb Mamoswine's Icicle Crash. Its Double-Edge hits 20% harder - Mamo would need a Life Orb, Adamant nature + 190 base Attack for its Icicle Crash to hits as hard as Mega Glalie's Double-Edge:
252+ Atk Refrigerate Glalie Return vs. 252 HP / 0 Def Mew: 226-267 (55.9 - 66%)
252+ Atk Refrigerate Glalie Double-Edge vs. 252 HP / 0 Def Mew: 264-312 (65.3 - 77.2%)
base 130: 252+ Atk Life Orb Mamoswine Icicle Crash vs. 252 HP / 0 Def Mew: 199-235 (49.2 - 58.1%)
base 190: 252+ Atk Life Orb Mamoswine Icicle Crash vs. 252 HP / 0 Def Mew: 265-313 (65.5 - 77.4%)
It now gets Freeze-Dry with its 120 Sp.Atk to hit the majority of bulky Waters trying to tank its Ice moves; Earthquake can deal damage to most Fire and Steels that resist Return + Freeze-Dry. And to finish off its moves, you can have Explosion to blow up and deal massive damage once you don't need Glalie around anymore. It also has Ice Shard, but it'll probably be too pressed for moveslots. Not to mention it gets Spikes + Taunt if you want a less offence-focused set. Most Defoggers don't actively want to switch into it to try and Defog them away anyway because most are Flying-types that hate Ice moves.
It's miles better than NU and too many people are focusing on "but who wants to explode their Mega?". Again, it's not gonna be OU, but it won't be staying in NU.