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Funny how that whole thing with Meloetta started with a schoolyard rumor with a couple students in the Blueberry Academy making reference to that exact spot. One talked about spinning, another talked about someone singing.
Yeah all Pokemon that weren't in SwSh got their pre-evo moves in BDSP. Masquerain (Sticky Web and a few others), Mismagius (basically everything) are two others. But they didn't get them back in SV. It's likely that the Level Up moves here ignored BDSP altogether because the Pokemon that were in...
I reckon they will fix a lot of the TM oddities such as Female Indeedee not learning Trick Room via TM (can only get it from a Raid). And hopefully the Pre-Evolution exclusive moves via relearn (Spore Breloom comes to mind). They did do so with the Isle of Armor for SwSh where they gave...
If I had to guess, maybe all moves get a smaller boost instead of the usual 50% (or 100% for matching type) but for Tera Blast (and likely Revelation Dance too), it'll get the 100% boost and hits neutral to everything. While also being Neutral to everything itself. That's my guess anyways.