Castle Garenbrig

Wildborn Preserver

Ok, so why can't I pump the Wildborn with Garenbrig mana? Is it somehow not an 'ability'?

It might not be... it’s a triggered effect.

Yeah it triggers ETB not on cast.

Yeah, Garenbrig is activated abilites, while preserver is a triggered ability, so can't be used for it

Thanks. What about mutate, is that an activated ability that can be cast with mana from Castle Garenbrig? Looking at Gemrazer
Found a shuffler 'bug'. Bolas's Citadel - comes in pairs. I kid you not.

Yes but mutate isn’t an activated ability, it’s an alternate casting cost

Activated abilities use the colon ":" and creatures are only creatures on the battlefield, so Castle Garenbrig would not work with cycling or other activated abilities off the battlefield.

Escape and mutate are alternate casting costs so they do work with Castle Garenbrig because you are casting a creature spell.

The weird part is that if I target a creature for my mutate spell and the creature is killed before mutate resolves, it comes down as its own creature instead of fizzling. I'm not complaining though.
Citadel's comes in pairs.

Back when Growth chamber guardian was playable there was a 98% chance your first 3 draws of the game would be the other 3

That is in the rules of mutate but not in the reminder text.