Players playing Monsters

[Regitnui]

This isn't about the bad kinds of players, but a different question. Would you allow a player to play a monster out of the MM?

One of my players is playing a Life Cleric of the Blood of Vol. He gained an item that gave him a thirst for blood, and although he's managed to hide it until now, the party will soon be in a locked room scenario where the only valid targets for feeding will be his party members or an oni. He's agreed with me that a good end for the character is attempting to feed on one of the other party members, and then being killed or escaping. The problem is that he misses the climatic boss fight.

My suggestion was that he play the oni, if only temporarily, as an ally to the party against the boss. Has anyone tried something like this before? I'd give him the stat block as his temporary sheet, until he can bring in the replacement he has planned.

[Sariel Vailo]

i have done this it was hard and doable albeit alittle difficult.

[JellyPooga]

If it's only temporary, just to get him involved with the final boss fight without straining the plot to breaking point by introducing a new character by way of crowbar, I don't see a problem with this.

The monster stat blocks are comprehensive enough for a short time; personality and background aren't really much of an issue except where the other party members are concerned e.g. if they're of the "Argh! It's a monster! Kill it! Kill it now! With Fire!" persuasion, then getting them to work alongside a monster could be an issue. The only other problem would be with character development, which is again solved by the temporary nature of the deal.

I say go for it.

[TheTeaMustFlow]

When we were playing Curse of Strahd, our party ended up with quite the coterie of NPC hangers-on, so the GM passed control of them to myself and another player (he still roleplayed them as npcs, but we controlled their actions, especially in combat). It worked quite well.