Can... the Variant Multiclassing Unchained rule be applied to monsters?

[JiCi]

Let's see if I got it right: you essentially substitute feats gained through regular leveling by class features.

Monsters gain feats using their racial HDs as levels, so... could a 3HD monster substitute its feat gained at "3rd level" for a class feature?

[Claxon]

Can it be? Probably. Should it be? It probably wasn't intended to.

As a GM you get to decide what to do for your campaign, but just remember that CRs for monster are built around certain things with the monster. Removing certain feats in exchange for class features could make the monster considerably stronger or weaker than its CR would otherwise suggest. Which isn't necessarily a problem, but you should adjust the CR of the creature based on the change it it's power level.

If you are a player, asking because you want to adjust an animal companion or something like that...I would say no. But again it would be up to any particular GM to make that decision.

I think the VMC rules were really only intended for PC characters.

[Dave Justus]

From a balance perspective it shouldn't matter. Theoretically the VMC class features gained are equal in power to the feats you trade for them. Obviously individual choices may be better or worse but on balance, if they were designed right then balance wise it should be fine.

Personally, I don't see any problem with doing this in general. For something like an Animal Companion I would require specific approval for a player to take it though, it would have to be something that made sense, and the AC would definitely have to have an int of at least 3.

[Ventnor]

It would be an interesting way to build a Monster with class levels without having to actually add class levels to them.

[JiCi]

I keep thinking that many high-level outsiders, dragons, monstrous humanoids, magical beasts and giants could use this mecanic.

Think about it, if you can't add class level because the CR would be too high and/or the abilities would be too weak for their current levels, why not replace feats with class features that actually scale with the HD?

A Dragon / Magus can work.
A Taiga Giant / Barbarian can work.
A Sphinx / Oracle can work.

[Archaeik]

The table lists "character level" not "hit dice", I'd strongly advise against applying VMC to replace feats from racial hit dice.

[LazarX]

A lot of monsters, especially outsiders are built to work with their hard coded feats. You start replacing them with VMC's things are going to go out of whack.

[eakratz]

The Monster Codex has templates for adding class abilities without altering hit dice. The CR is modified though. I've only used it twice on skulks, but it does the job well.

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