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I'm currently running a mega dungeon in 5e D&D, and my players have recruited some monsters into their service. I have been building encounters using the dungeon masters guide rules (pg. 81-84), but these only account for groups of player characters. How should I recalculate the encounter difficulties that I have planned when they also have some recruited monsters with them?
Options I have considered are shifting the encounter multiplier (pg. 82) according to the party size paragraph (pg. 83), but this fails to account for the inherent weakness of the recruited MOBs,
Alternatively, I could maybe add the modified experience total of the group of MOBs to the parties XP thresholds, as modified XP is probably a fairly accurate guage of additional party ability (probably without including them in the party size)
If anyone has done this before, knowing what worked would be nice, otherwise I'll use my best judgement and comment later on how well it worked out