Armblade Lance

An armblade is a magic weapon that attaches to your arm, becoming inseparable from you as long as you're attuned to it. To attune to this item, you must hold it against your forearm for the entire attunement period. As a bonus action, you can retract the armblade into your forearm or extend it from there. While it is extended, you can use the weapon as if you were holding it, and you can't use that hand for other purposes.

Special: You have disadvantage when you use a lance to attack a target within 5 feet of you. Also, a lance requires two hands to wield when you aren't mounted.

Reach: This weapon adds 5 feet to your reach when you attack with it, as well as when determining your reach for opportunity attacks with it.

Proficiency: martial, lance Source: Eberron: Rising from the Last War p. 276, Wayfinder's Guide to Eberron p. 120, Player's Handbook (2014) p. 149