Demon Armor
Armor (plate), very rare, requires attunement · 2014 rules, SRD 5.1
+1 AC; understand and speak Abyssal; claws deal 1d8 slashing and count as +1 weapons. Curse: disadvantage vs demons' spells and attacks; can't remove it.
Also in the 2024 rules (SRD 5.2).