can a keyrune still tap for mana as a creature?
can a keyrune still tap for mana as a creature?
Sure. Becoming a creature doesn't make it lose any other abilities it has.
Notably, you can animate Selesnya Keyrune, block a creature, tap the Keyrune for a green mana, and use that green mana to cast Giant Growth on the Keyrune.
If you were to find a way to give the Keyrune vigilance, you could attack with it, tap it for mana, and cast Giant Growth on it then.
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