Rules edition: This guide compares the Firbolg options from Volo’s Guide to Monsters (2016, with later errata) and Mordenkainen Presents: Monsters of the Multiverse (2022). Their ability scores and limited-use traits differ. Use one source’s version consistently; do not combine the two stat blocks.
Shared basics
Both options describe a Medium Firbolg with a 30-foot walking speed. A Firbolg is not a Large creature: its height does not change the spaces it occupies or the size category used in combat. Powerful Build lets you count as one size larger only when determining carrying capacity and the weight you can push, drag, or lift. Firbolgs do not gain darkvision from these traits.
Both versions include Firbolg Magic, Hidden Step, and Speech of Beast and Leaf, but the details differ. Volo’s original ability increases are +2 Wisdom and +1 Strength; the published Volo’s errata removes the Alignment trait but does not change those increases. The MotM version instead uses flexible ability increases. Check the chosen source and any optional character-creation rules when adapting an older character sheet.
Volo’s Firbolg: legacy traits and errata
The original Volo’s Firbolg increases Wisdom by 2 and Strength by 1. The published Volo’s errata removes the Alignment trait but leaves these ability increases unchanged. Use the printed increases unless your DM allows Tasha’s optional custom-origin rules or another approved adaptation.
Volo’s Firbolg Magic uses Wisdom. You can cast detect magic and disguise self once each with the trait, regaining the uses after a short or long rest. The disguise can make you appear up to 3 feet shorter or taller than normal. Hidden Step is a bonus action that turns you invisible until the start of your next turn or until you attack, make a damage roll, or force a creature to make a saving throw. You can use it once per short or long rest.
Monsters of the Multiverse Firbolg
The 2022 version uses flexible ability increases: increase one score by 2 and a different score by 1, or increase three different scores by 1, following the character-creation method your table uses. Firbolg Magic lets you cast detect magic and disguise self; choose Intelligence, Wisdom, or Charisma as the spellcasting ability. Each spell can be cast once per long rest with the trait, and you can also cast it with spell slots. The special height adjustment for disguise self remains.
MotM Hidden Step keeps the bonus-action invisibility and the same end conditions, but its uses equal your Proficiency Bonus and return after a Long Rest. This is a material resource change from the legacy short-or-long-rest version. MotM Speech of Beast and Leaf lets you understand and verbally communicate with Beasts and Plants as if you shared a language, and gives you advantage on Charisma checks to influence them. It does not compel them to help; what they know and can convey depends on the individual creature or plant.
Using Hidden Step and Firbolg Magic
Hidden Step’s invisibility is brief and ends early if you attack, make a damage roll, or force a saving throw. It can help with concealment or repositioning, but moving while invisible does not automatically prevent opportunity attacks. The feature uses a bonus action, so it competes with other bonus-action features on that turn.
Detect magic and disguise self are useful in different situations: one helps notice magic, and the other changes your appearance without changing your body or size category. The height adjustment can help a tall Firbolg blend in, but it does not make you Small or alter your game statistics. Spell duration, concentration, and other effects follow each spell’s own rules.
Choosing a class and roleplay approach
With the legacy Wisdom increase, classes that use Wisdom may fit naturally, while the errata-adjusted Dexterity increase and MotM’s flexible scores support a wider range of builds. Hidden Step and Firbolg Magic offer utility to many classes; Powerful Build can matter when a character must carry or move heavy objects. These are options, not class restrictions or a guarantee that one combination is strongest.
Firbolg lore and personality depend on the campaign setting. The older Volo material is framed around its own sourcebook’s perspective; MotM presents more setting-flexible material. A Firbolg may be reserved, outgoing, scholarly, ambitious, or anything else that suits the character. Choose how the character relates to their community rather than treating a cultural description as a required personality.
