Hammer of Thunderbolts
Weapon (maul), legendary · 2014 rules, SRD 5.1
+1 attack and damage. Attuned while also wearing a belt of giant strength and gauntlets of ogre power: Str +4 (max 30), giant slayer (DC 17 Con or die), thrown thunderclap (5 charges).
Also in the 2024 rules (SRD 5.2).