Gemrazer (Ikoria: Lair of Behemoths) - Andrew Huerta
More cards with art by Andrew Huerta on Scryfall

seen from Maldives
seen from China

seen from Brazil
seen from United States
seen from South Korea
seen from United States

seen from T1
seen from United Kingdom
seen from China

seen from Germany

seen from Malaysia
seen from United Kingdom
seen from China

seen from Malaysia

seen from Israel
seen from Israel
seen from Argentina
seen from United Kingdom
seen from Israel

seen from Mexico
Gemrazer (Ikoria: Lair of Behemoths) - Andrew Huerta
More cards with art by Andrew Huerta on Scryfall
Gemrazer
Artist: Evan Shipard TCG Player Link Scryfall Link EDHREC Link
Playing a Meren of Clan Nel Toth Commander deck with her in play and at least 4 counters. Can I Mutate Gemrazer out of the graveyard onto a creature I have in play? I’m guessing no, but I am curious if running Mutate cards in this type of deck would actually work.
No, this doesn't work.
Meren's ability returns the creature card to the battlefield rather than casting it, and mutate only works via casting for the mutate cost. (Even she did have you cast it for free, you wouldn't be able to mutate with it because mutate is an alternate cost and you'd already be casting it without paying its mana cost, which is also an alternate cost and you can't pay two different alternate costs for the same spell.)
What you can do is just return the card to your hand and then cast it for its mutate cost. You just still have to pay mana, which is worse than free but better than being forced to put it into play as its own body, I guess?
Gemrazer by Svetlin Velinov
Gemrazer (Ikoria: Lair of Behemoths) - Andrew Huerta
I'm curious if this is a glitch in mtg arena or some layers thing I'll not understanding. I have Vulpikeet on the field. Opponent casts Frogify on it which makes my creature a 1/1 with no abilities. I later try to cast Gemrazer via mutate onto Vulpikeet to use the Gemrazer Mutate trigger to remove Frogify. But, the new mutation is still just a 1/1 with no abilities and Frogify remains. I thought creatures could still gain ability after losing them and Gemrazer having later timestamp would help.
That interaction is working as intended.
While it’s true that effects that add and remove abilities apply in timestamp order, mutate doesn’t work by giving abilities and the like, but rather by changing the copiable characteristics of the mutated creature. Since mutate is a copy effect, it applies earlier than Frogify’s effect and so any ability that would be gained by the creature is stripped away by Frogify before it can be relevant.