I keep buying objects that I think are weapons only to be disappointed afterward. Some items have very misleading names and descriptions (e.g. Illumis Nuclear Explosive Goo), so is there any way to prevent this?

There's a list of weapons on SubetaHQ.

Another related question: is said non-weapon item intented to be usable or purely decrorative?

Illumis Nuclear Explosive Goo should actually be a weapon. Did you put it in the Armory?

There is no option to put it in the armory; is there an item limit for the armory?

Hmm. Allow me to call over our Battle Admin. I'm not terribly familiar with the Coliseum.

Thank you.