Minsc is a beloved companion inBaldur’s Gate 3, but many players have a hard time taking him seriously. It’s quite easy to write off Minsc’s claim that his rodent companion, Boo, is a miniature giant space hamster - especially ifBG3was your first introduction to theBaldur’s Gatesetting.
The idea that Boo, a seemingly regular hamster, is smarter than Minsc is usually played for laughs- but several clues point to him having intelligence that’s much higher than an ordinary hamster, and that Minsc’s perception of him has nothing to do with his head injury.

Minsc Wasn’t Lying - Boo Could Actually Be A Miniature Giant Space Hamster
Despite The Confusion Of Your Companions, Miniature Giant Space Hamsters Do Exist
Firstly,giant space hamstersthemselves are undoubtedly real inDnDlore and were first introduced in2e.Lae’zel even notes that they’re a common food source for githyanki,though she has yet to come across a miniature version - let alone one that can engage in conversation. She concludes that Boo is a very rare specimen, or just a regular hamster.
However, it seems like this isn’t the norm for all githyanki - as Reddit usertheREALvolnodiscovered,you can find grilled miniature giant space hamsters in Crèche Y’llek.So, we know miniaturevariants of giant space hamstersdefinitely exist as well.

Boo has evidently lived for much longer than a hamster should be able to, though you could easily chalk this up to the fact thathe and Minsc were petrified, which paused their aging process.
Still,BG3takes place in 1492 DR, and Minsc was broken out of petrification sometime in the 1480s. This suggests thatBoo has possibly already exceeded the typical 2–3 year lifespan of a normal hamster, which would make sense if he were in fact a giant space hamster, which often live up to 18 years of age.

Even though Boo chooses to talk to Minsc, unlike other rodents, the player cannot useSpeak with Animalson him, which usually allows players to converse with beasts.If you’re a druid, you can ask Minsc why you can’t understand Boo- but as you can probably imagine, Minsc has no idea either.
Perhaps this could be a hint that Boo isn’t considered a beast inBG3,and his apparent stats are not indicative of his true nature.BG3stretches the usual definition of “beast,“and lets playerstalk to Owlbearsand Displacer Beasts - creatures that are normally classed as monstrosities.
As a sentient being, he likely makes a conscious effort to only talk to Minsc, and simply isn’t interested in conversation with anyone else.
One Easily Missed Book Gives Us All The Information We Need
Boo’s True Identity Isn’t Hidden Information
The book “A Primer on Mythical Beasts” can be found in the Emerald Grove, and is also sold by Nansi Gretta, the owner of The Bibliophile fromthe Lower City in Act 3.Opening it will reveal a passage from chapter 5 about miniature giant space hamsters, which seems to perfectly mirror Minsc and Boo.
“Very little is known about this particular cryptid, though stories say they tend to choose well-muscled human males as their steeds when they deign to visit this plane. According to legends, this creature retains a wellspring of indescribable power known only to itself, though it provides its steed with perhaps mystical, perhaps mundane courage. Unsubstantiated rumors claim the creature has a taste for human eyes.”
-A Primer on Mythical Beasts, Chapter 5 - Miniature Giant Space Hamster
It’s not overly clear if this is just a direct observation of Minsc and Boo themselves, but other pieces of literature that mention giant space hamsters are few and far between.
Though it’s fun to speculate based on in-game evidence,Boo’s true identity was actually confirmed beforeBG3ever came out.A short video uploaded to the officialDungeons & DragonsYouTube Channeldetailed the backstory of miniature giant space hamsters.
The miniature variant of the species came about after some giant space hamsters were shrunk by wizards, which unintentionally increased their intelligence by drastic measures and allowed them to communicate through telepathy. Boo is mentioned as a specific example, which confirms that the Boo we meet inBaldur’s Gate 3is far from a regular rodent.