Animal Companion Size Increase?

[Gerrtt]

Maybe this is a dumb question and one that never really occurred to me...

When a druid levels up and their animal companion gets bonus HD from improving, does their size increase if they animal gets the appropriate number to change size categories?

For example, at level 3 a druid's animal companion gets +2 HD, and if you have a wolf that bumps your wolf up to 4 HD from 2.

Does that mean that the animal companion gets a feat, a stat increase, and a size increase?

[ddude987]

They do not however if your DM abides by the rule of cool they can

[Maginomicon]

When a druid levels up and their animal companion gets bonus HD from improving, does their size increase if they animal gets the appropriate number to change size categories?No.

When you add Hit Dice to a druid’s (or ranger’s) animal companion as the master’s level goes up, does the animal get any bigger? For instance, when a druid has a wolf companion, the wolf starts out with the standard 2 Hit Dice and is size Medium. By the time the druid is 3rd level, the wolf has 2 bonus Hit Dice. According to the wolf entry in the MM, an “advanced” wolf with 4 Hit Dice would be Large. Is the example companion wolf also Large?

An animal companion doesn’t get bigger when it adds extra Hit Dice for the master’s levels. The advancement entries for creatures, and the rules for advancing monsters, refer to unusually powerful specimens that are simply tougher (and perhaps bigger) than normal for their kinds.
In other words, the advancement entries are optional GM-only rules for size when encountering those creatures in the wild.

[Gerrtt]

But they do get feats, skill points, and stat adjustments as normal?

[DeltaEmil]

An animal companion gains additional skill points and feats for bonus HD as normal for advancing a monster’s Hit Dice. It does not gain any stat increases from the bonus HD, but its Strength and Dexterity are adjusted according to the druid's class level.

[Gerrtt]

I figured as such. I was making a druid enemy for my players and its animal companion was really getting out of hand... I knew they were strong, but sheesh. Glad I was making an error.