Sure, it could: "A spellcasting creature that lacks hands or arms can provide any somatic component a spell might require by moving its body." Unfortunately, it will have difficulty with material components and foci so it will have to choose its spells appropriately. Also, it has tongues always active, so it must be able to speak somehow. I thought I remember it saying somewhere that they "speak" by vibrating their bodies?Grog said:Without hands, it couldn't cast any spells with somatic components. (And, can Lantern Archons speak? If not, no verbal components either).
That's almost a non-issue with many builds, particularly those who don't plan on getting into melee anyway.moritheil said:Also, no one seems to have mentioned the downside that a lantern archon does not threaten a space and can never take AOOs (unless, presumably, one builds a peerless archer lantern archon.)
Infiniti2000 said:That's almost a non-issue with many builds, particularly those who don't plan on getting into melee anyway.
moritheil said:It's a nonissue for a caster, but a huge issue for a rogue (one of the suggested uses.) For example, it's impossible to build into (or use) the opportunist/sneak attack AOO feat chain. And the light rays have a limit of 30', which means that there's no point in playing a sniper rogue - the entire point of that is to arrange things so you can sneak attack from 60' or more.

(Dungeons & Dragons)
Rulebook featuring "high magic" options, including a host of new spells.