At this point, it is a good idea though not necessary to go to one of the Pso'Xja towers to obtain Chips needed for a permanent key item. Anyone doing this mission needs one; the color does not matter be it (Gray Chip, Carmine Chip or a Cyan Chip).
If you wish, you may drop into the hole on the right side of the map at (I-8). This drops you into a higher level area with more Diremite spawns. Be careful though as the Diremites in this section are aggressive towards high-level characters. You may want to apply Sneak before dropping into this area, as there is one Diremite spawn at the spot that you'll land.
Sneak and Invisible are a good idea for characters at low enough level. There is one Snowball that detects spellcasting as well as by sight. In the second area only sneak is required and after that it is no longer needed.
To get to The Shrouded Maw, pass through smokey "walls" of different color in the following order:
After the last black wall, you will be in the fourth area. Use the elevator here to go to the lower level.
Note that the Mission-version and Avatar-fight version of Diabolos are much different and therefore have different resistances. The Mission-version of Diabolos can be stunned with stun skills and weaponskills. All stun have a chance to fail, however methods that have been tried and tested to Stun this version of Diabolos with some success are:
You start on a platform above the battlefield. Once someone falls down, everyone else is dragged down as well, and the battle begins.
The party may get Draw In by Diabolos, which will generally happen after the first person engages. If it doesn't Draw In immediately, it will do it once any player on the top ledge gets Enmity. If Draw In is used, then you may be placed in the center of the arena and Diabolos will be in front of you, or your party members may be Draw In scattered around the area. If this happens, look for the portal which will indicate the front of the battlefield, and then situate yourself on the non-dropping tiles you might have agreed upon before starting the fight.
If anyone should remain on the upper level after the initial Draw In, for example if a party member drops out of party after entry but before attacking Diabolos, Diabolos will continue to use Draw In repeatedly throughout the fight in vain attempt to bring the player upstairs down to his battlefield. This can create chaos as party members are repeatedly moved to and fro by repeated Draw In. The person above, being out of party, will never be pulled down but neither will Diabolos stop the attempts to bring them down.
The battlefield consists of 25 floor squares which may be removed by Diabolos during the fight. If you fall or are on a square that is removed, you will be eaten alive by about eight waiting and hungry Diremites.
If you are strong enough to withstand the Diremites' attacks long enough, you can run out of the lower arena, down a short hall and into a room, and them up some long staircases to reach a balcony above Diabolos. Re-engaging Diabolos will de-aggro all Diremites from you.
You can see which tiles will disappear before you drop into the arena; the tiles which will disappear have a thicker outline. The tiles will light up momentarily before they disappear though the light-up-to-drop time is extremely fast so make sure you are not on one.
The tile-placement may change from fight-to-fight. Due to this it falls into being dependent on individual player experiences and therefor all tile-placement reports should be placed on this wiki's Talk page for Tile-arrangements.
Do not forget to go talk to Monberaux after the fight.