Mercenaries and Youkai also have the option to sub attack all of a sudden, so more than likely there may just be something with MMA janking since the update.
Debug doesn't give any special info when using the sub attack on a mercenary.
Snakeman Knight's turn.
Scarebear's turn.
System: Player debug is now on.
System: Debug: Movement: In a battle and no tactarg or tac_move.
System: Debug: Movement: In a battle and no tactarg or tac_move.
Scarebear attacks Snakeman Knight with Scareclaw!
Snakeman Knight takes 87 Slash physical damage.
Debug doesn't give any special info when using the sub attack on a mercenary.
Snakeman Knight's turn.
Scarebear's turn.
System: Player debug is now on.
System: Debug: Movement: In a battle and no tactarg or tac_move.
System: Debug: Movement: In a battle and no tactarg or tac_move.
Scarebear attacks Snakeman Knight with Scareclaw!
Snakeman Knight takes 87 Slash physical damage.