If Muraganda Eldrazi is countered or otherwise leaves the stack in response to that triggered ability, the triggered ability will resolve is normal
Enter Mine, Mine, Mine
If, during a player's declare attackers step, a creature that player controls that's been goaded is tapped, is affected by a spell or ability that says it can't attack, or hasn't been under that player's control continuously since the turn began (and doesn't have haste), then it doesn't attack
2023-04-14 Battles can't attack or block, even if one also becomes a creature
I dont believe Ive made it perfectly, and Im always open to feedback
Sephiroth, the Savior is arguably one of the most iconic villains you could put on a Magic card, and its only fitting its on Atraxa, Grand Unifier