The Ninth World, Homebrew, Borderlands 2, The Sky Fortress
Alien Beast. Though King Mong is a monstrosity, spells that effect or work on Beasts works on King Mong. Legendary Resistance (3/Day). If King Mong fails a saving throw, he can choose to succeed instead. Reckless. At the start of his turn, King Mong can gain advantage on all melee weapon attack rolls he makes during that turn, but attack rolls against him have advantage until the start of his next turn. Mythic. King Mong is an exemplar of his species and has maximum hit points. Siege Monster. King Mong deals double damage to objects and structures.
Multiattack. King Mong makes four attacks, one of which can be a rock-throw attack. The first of those attacks that hit deals an extra 18 ( 4d8 ) damage if King Mong has taken damage since his last turn. Fist. Melee Weapon Attack: 1d20+10 to hit, reach 15 ft., one target. Hit: 4d8+6 bludgeoning damage. On a critical hit, the target is stunned until the end of its next turn by the violence of the blow. A creature hit by two fists attacks is grappled and can be tossed. Rock-Throw. Ranged Weapon Attack: 1d20+10 to hit, range 60/240 ft., one target. Hit: 4d10+6 bludgeoning damage. If the target is a creature, it must succeed on a STR saving throw or be knocked prone. On a critical hit, the target is stunned until the end of its next turn by the violence of the blow.
Eat Dirt! As a reaction to being hit by a ranged attack (including a spell), King Mong can use Rock-Throw against the triggering attacker.
King Mong can take 3 legendary actions, choosing from the options below. Only one legendary action option can be used at a time and only at the end of another creature’s turn. He regains spent legendary actions at the start of his turn.
Where King Mong lairs, he is accompanied by a band of bullymongs. These include 1d4 adults (use Giant Ape) and 1d6 welps (use Ape). If at the start of King Mong's turn, the encounter timer is at 1 (1d4 timer) another 1d4 adults and 1d6 welps join the battle. They disperse if killed.
Wasteland, technologcal ruins