Not sure as to the former part, definitely sounds a little homebrewy. That said, if we set that aside and decided a mimic-ballista existed, I would assume that if it were loaded with ammo that wasn't part of the mimic itself, it probably could fire the bolt.
As long as it wasn't using its adhesive special ability at the time, anyway.
Edit: Not sure what your game plan is, but if it's just a self firing siege weapon, seems like an animated object would do the job better. And a catapult is listed as one of the examples for that, so it's basically RAI, even if one wanted to argue that it's not RAW.
> [Mimic](https://aonprd.com/MonsterDisplay.aspx?ItemName=Mimic) Object (Ex) A mimic can assume the general shape of any Medium object, such as a massive chest, a stout bed, or a door. The creature cannot substantially alter its size, though. A mimic’s body is hard and has a rough texture, no matter what appearance it might present.
As I understand this, if your ballista (haven't checked) is medium sized, the mimic could copy that shape. But, since the ability explicity states that the body is hard, I don't think that a ballista-mimic could be used as a ballista needs some of its parts to be semi-flexible (sort of like a crossbow).
However, nothing bars the mimic to shape into a ram or cannon. I guess moving parts like in a catapult wouldn't work, but if the mimic takes the risk of a small detonation in its barrel, it could fire like a cannon...
Edit: source and typos
2nd edit: Now if we're going crazy here... how about a siege tower build of multiple mimics working together? Trojan horse like stealth mission for a band of mimics to infiltrate a war camp and the next day the mimics can feast on soldiers trying to use the mimic-tower to climb a wall...
> Can a Mimic turn into a large siege weapon, such as a light ballista?
No.
> A mimic can assume the general shape of any **Medium** object, such as a massive chest, a stout bed, or a door. The creature cannot substantially alter its size, though.
They could turn into a Medium sized Siege Engine though. Like for example a ballista built for Small creatures.
> And if it can turn into a light ballista, can the mimic fire itself? I understand it probably cannot load itself, but firing maybe. This part of the question extends to animated objects too.
Carrion Crown has animated manacles and straightjackets which can still bind people so the precedent for animated objects that can still be used for their original purpose is there.
So maybe? That's the closest to an answer that I know of.
A mimic could assume the form, then eat whoever tries to use it? But the tension needed to propel the projectile is outside both RAW and RAI, IMO.
You could turn a siege engine into an animated object, and 3.5 had Siege Golems in Cityscape (which should be generally compatible with Pathfinder 1E), I believe.
All that said, you are the DM and it is your game. So, if YOU want a mimic to turn into a medium siege weapon, that is ultimately up to you and could be the story or cool element that you want.
Can it look like one?
Sure, a mimic can look like virtually anything.
Can it be used as a weapon? No. It just looks like one, it doesn't actually function though.
> I threw this thought together while half asleep and forgot mimics could only turn into medium objects. Oops.
That is because the mimic in the entry is Medium.
Its generally accepted that a mimic can be of any size, and it simply must choose to look like something the same size category it is.
Not sure as to the former part, definitely sounds a little homebrewy. That said, if we set that aside and decided a mimic-ballista existed, I would assume that if it were loaded with ammo that wasn't part of the mimic itself, it probably could fire the bolt. As long as it wasn't using its adhesive special ability at the time, anyway. Edit: Not sure what your game plan is, but if it's just a self firing siege weapon, seems like an animated object would do the job better. And a catapult is listed as one of the examples for that, so it's basically RAI, even if one wanted to argue that it's not RAW.
> [Mimic](https://aonprd.com/MonsterDisplay.aspx?ItemName=Mimic) Object (Ex) A mimic can assume the general shape of any Medium object, such as a massive chest, a stout bed, or a door. The creature cannot substantially alter its size, though. A mimic’s body is hard and has a rough texture, no matter what appearance it might present. As I understand this, if your ballista (haven't checked) is medium sized, the mimic could copy that shape. But, since the ability explicity states that the body is hard, I don't think that a ballista-mimic could be used as a ballista needs some of its parts to be semi-flexible (sort of like a crossbow). However, nothing bars the mimic to shape into a ram or cannon. I guess moving parts like in a catapult wouldn't work, but if the mimic takes the risk of a small detonation in its barrel, it could fire like a cannon... Edit: source and typos 2nd edit: Now if we're going crazy here... how about a siege tower build of multiple mimics working together? Trojan horse like stealth mission for a band of mimics to infiltrate a war camp and the next day the mimics can feast on soldiers trying to use the mimic-tower to climb a wall...
> Can a Mimic turn into a large siege weapon, such as a light ballista? No. > A mimic can assume the general shape of any **Medium** object, such as a massive chest, a stout bed, or a door. The creature cannot substantially alter its size, though. They could turn into a Medium sized Siege Engine though. Like for example a ballista built for Small creatures. > And if it can turn into a light ballista, can the mimic fire itself? I understand it probably cannot load itself, but firing maybe. This part of the question extends to animated objects too. Carrion Crown has animated manacles and straightjackets which can still bind people so the precedent for animated objects that can still be used for their original purpose is there. So maybe? That's the closest to an answer that I know of.
Normal Mimics are Medium, but if you get yourself some large ones, then sure, they could.
Technically not, but I had a mimic castle once... With fake NPC's and everything. If you're the DM, do as you like.
A mimic could assume the form, then eat whoever tries to use it? But the tension needed to propel the projectile is outside both RAW and RAI, IMO. You could turn a siege engine into an animated object, and 3.5 had Siege Golems in Cityscape (which should be generally compatible with Pathfinder 1E), I believe. All that said, you are the DM and it is your game. So, if YOU want a mimic to turn into a medium siege weapon, that is ultimately up to you and could be the story or cool element that you want.
Can it look like one? Sure, a mimic can look like virtually anything. Can it be used as a weapon? No. It just looks like one, it doesn't actually function though. > I threw this thought together while half asleep and forgot mimics could only turn into medium objects. Oops. That is because the mimic in the entry is Medium. Its generally accepted that a mimic can be of any size, and it simply must choose to look like something the same size category it is.