This may sound crazy but it almost looks like this sequence.
Rev was mis-aligned as hammer die.
Collar clash transferring part of UNI tot he edge of the collar.
Collar counterclash transferring part of UNI from the edge of the collar back to the die but offset.
Rev die re-aligned but face slightly out of parallel with the obv die.
Coin is struck showing collar counterclash with missing rim from out of parallel dies.