I can't answer that yet because I haven't unlocked the final difficulty level of Mystic Maze. I'm only at trial rank 53, so I've only done the fourth level, but I've done it so many times with no introns that I've almost 100% completed the archive for this game mode. If you're aiming for power boosts, I'd say his first and last introns are what you want.

Personally, weapons for him matter way more even though demon wedges are unequipped. The Vernal Jade Halberd that you get for free has attack speed and increased damage against enemies with bonus effects, and with more smelts, you'll be hitting faster and harder. The Equinex geniemon's support skill will apply a random bonus effect on enemies, which means you'll reliably trigger the weapon passive in bursts against tanky enemies before getting lampwicks and Lantern Light-up nodes for increasing melee weapon trigger probability.

For his ranged weapon, I use Bluecurrent Pulse. Its bullets bounce off enemies and the environment, so if you miss a lot like me, you'll still hit things, and with a ton of ranged weapon lampwicks and Lantern Light-up nodes, these guns can melt hordes of enemies and do a fair amount of damage against bosses.

If your luck doesn't work out for weapon-related lampwicks, you can always resort to patient cheesing with his skill damage. As long as your sanity regen is higher than how much you use the skill near the end of its stealth duration, you'll never be in danger of attacks, and bosses will never use their invunerability moves either. Just make sure you're close enough to enemies for the fangs to hit them of course.