Ring of the Arcane Berserker (Patreon)

Ring, rare (requires attunement by a barbarian)

This dark silver ring is decorated by a metallic skull with an amethyst gemstone embedded in its forehead. While wearing the ring, you can use an action to cast the chill touch spell (+5 to hit with ranged spell attack) from it.

This ring has 3 charges and regains 1d3 expended charges daily at dawn. While wearing it, you can cast a spell even if you're raging by expending 1 of the ring's charges as part of casting the spell. If you do, your rage does not end at the end of your turn as a result of not attacking a hostile creature. In addition, you can concentrate on spells while raging, but have disadvantage on Constitution saving throws to maintain your concentration on them when you take damage.

"What's he doing now? Why's he waving his hands and axe around like that and screaming?"

"Oh, he's trying to cast a spell. He just got that ring from Ilra back in town. He stopped listening before the part about how to actually use it."

"So, just to make sure...he doesn't know any spells, right?"

"Oh heavens no. But as far as he knows, that's all we do when we cast one."