Start a brawl game with Arna Kennerud
Play a creature
Play and equip Mystery key
Attack with the creature, Mystery Key triggers and is sacrificed
Play Arna Kennerud
Play Sword of Ice and Fire
Play Forged Anew, bringing back Mystery Key
Equip the Sword using Forged Anew's 0 mana alternate cost
Game immediately jumps to next phase, as if I have no mana available
I still have mana available - unable to equip Mystery Key, even though Forge Anew should let me

  PC - Steam

  I still have mana available but I am unable to equip Mystery Key, it is behaving as if i have no mana available

  Should be able to equip Mystery key with my remaining mana, at instant speed

  Add any relevant screenshots/videos

  If you found a workaround, please add workaround steps. - N/A