ToME: the Tales of Maj'Eyal

Higher Cursed character.
I bought a +19 lightning on melee hit shield and could not afford a good 1-hander so I just wore the shield.
To my surprise, every couple of attacks, my character breathes lightning instead of melee attacking.

Is this some sort of hidden feature, or just a silly bug?

Gloves have a lot of egos that perfom talents when you performed unarmed attacks with them, which is what's happening when you're equipped with only a shield. Usually only Brawlers and characters that take the Flexible Combat prodigy can see the combat stats on gloves.

http://te4.org/characters/156118/tome/d ... 496e09c6f6

I'm wearing storm leather gloves of strength. Is this the reason?

Yep, exactly so. Gloves can actually have pretty fantastic on-hit effects, but most characters stink with them too much to give up a weapon. You might also notice random effects like these when you're disarmed (happens a lot when you run into enemies stocked with Acid Wave runes).

Thank you for clearing that up!