Kinda like a beast companion but… well, you know, it’s a brick…
The brick wants to be thrown. At walls, through windows, at someone’s head, it doesn’t really care at what it’s being thrown as long as it is intentionally violent.
If you don’t throw your brick companion violently enough or often enough it will make its displeasure known. If it’s in your bag, it will bounce and break any fragile stuff you might have. If it’s at your feet (because the brick companion can totally follow you around) it will make you stumble or hit your toes. If you still ignore it, the brick will find a more suitable companionship. A brick companion has its needs.
Brick stats as a weapon: 1d6, thrown, range 10-30′
The brick will slide/bounce back to its companion’s feet and be ready to be thrown again for next round.
It’s lame? Yeah, yeah, it is.
How about it throws itself?
It can totally do that. You must command it: “briiiiiiiiiick attaaaaaack!!!”.
Making a command take your own action so… yep, still totally lame.
Heck, it’s just a fucking brick, what did you expect?