I consider Monster Players separate from NPCs or Non-Player Characters. Non-Players Characters are usually played by the Dungeon Master and they help to flesh out the plot or provide key information or assistance to the players. NPCs are pretty shallow characters with a single purpose due to all the items on the Dungeon Master’s plate.

Monster Players are something totally different. As a Dungeon Master, I love calling on some experienced D&D players to be a special guest in the campaign and play a significant monster, boss, or BBEG.

Sometimes as a Dungeon Master it is a lot of work to manage the plot, story, battle field, combat, and interactions. This can limit the amount of creativity the Dungeon Master can use with the boss monsters or even the BBEG. The Dungeon Master plans ahead and tries to craft a combat plan, but usually the actions could be more diverse if the Dungeon Master didn’t have to deal with everything else on his plate. This is especially true for BBEG that have a wealth of options and legendary actions.

Also some Dungeon Masters play some monsters better than others. In only makes sense that a Dungeon Master can’t play them all equally well and it makes sense to call on a Monster assistant.

The ultimate solution to this is to have guest Monster Players that research the boss or BBEG, refine their motivations, and play alongside and against the players controlling the boss or BBEG. This role is best played by an experienced D&D player who has experience as a player and as a Dungeon Master. That way the player understands the logistics and objectives from both sides.

I don’t know why I didn’t think of this earlier in my DM career. Most people acknowledge the sheer joy of the creativity and innovation by players in their games – why wouldn’t we extend this to the crucial Monster characters to make the encounters as creative, dynamic, and innovative as possible.

This occurred to me after some experiences where the BBEG combat wasn’t as challenging as I thought it should have been. This was too surprising as the players were committed to their players while I as the Dungeon Master was committed to many things beside just the BBEG. As a DM that places a lot of effort into story and interactions, I found I didn’t have all the time and energy needed. This option corrects that in spades.

For an additional benefit, I search out Monster players with specialty in playing certain monsters. It can be a special skill to research and understand how best to play a Dragon, Demon, or Lich. Think Benedict Cumberbatch as Smaug – I could only dream of playing Smaug 1/100 as well.

Why not call on a Monster Player and take your climatic battle up a notch?