Remain in Battle Screen After Killing All Enemies?

Try approaching it from Terra's targets, rather than Terra's script itself.

Monster 377 (Soldier) is the one that gets used for this (I think.  It starts with Stop, and as far as I know that's the fight that has a monster start with Stop).

Try adding this to its monster script:

Code:

FC 12 00 00    {Is this monster dead?}
FC 13 01 00    {Are there no monsters left?}
F7 11          {Trigger event "Burn it all!"}
FB 02 00       {End battle}

Just make sure to remove the event trigger from Terra's end.
I don't know if this'll work, but it's worth a shot, right?