@Jack 360: quoting Genesis:
"Make sure if your gonna use the monster editor to un-slot your monsters first then hack your monsters".
Also make sure you don't have a chocobo at Serendipity, it will give you the same problem. By the way, be sure to make a backup of your savegame before editing.
@ Choirboy: Just follow Genesis instructions and make a backup before editing to avoid any problem.
@boombox2012: when you stagger him, focus only on valfodr, bring the bonus chain to 999 and then try to deal as much damage as you can; use imperil and deprotect on him, chichu, omega or lightninhg as commando and be sure to have at least brave and faith when you stagger him (using a Gahongas/Yakshini or a chief goblin-clodbrust combo), it won't take long at level 45.
You can team pulse gladiator as many time as you need (i teamed it many times), but you can have only one crystal, so if you already have a pulse gladiator you cannot team another one, this can be done only with chocobos.