Annam the All Father, Demigod of the Forge

Innate Spellcasting. Annam’s innate spellcasting ability is Strength (spell save DC 23, +15 to hit with spell attacks). He can innately cast the following spells, requiring no material components:

At will:  Heat Metal, Conjure Volley, Mold Earth, Earthbind, Cordon of Arrows, Telekinesis (metal only)

1/day each: Gravity Fissure, earthquake, Gravity Sinkhole, blade barrier

Immutable Form. Annam is immune to any effect that would alter his form.

Legendary Resistance (3/Day). If Annam the All Father fails a saving throw, he can choose to succeed instead.

Magic Resistance. Annam has advantage on saving throws against spells and other magical effects.

Reflective Skin. Annam's skin is made of thick metal. Any time Annam is hit by a line spell, or a spell that requires a ranged attack roll, roll a d6. On a 1 to 5, Annam is unaffected. On a 6, Annam is unaffected, and the effect is reflected back at the caster as though it originated from Annam turning the caster into the target.

Siege Monster. Annam deals double damage to objects and structures.

Dancing Weapon. Annam the demigod of the forge can control a weapon at least partially made of metal that he can see within 30 feet. If the weapon is being held by another creature, they must make a strength saving throw DC 20 or have it ripped from their hands. Once energized with divine magnetism, the weapon begins to hover, flies up to 30 feet, and attacks one creature within 5 feet of it. The weapon has a +17 to hit, reach 5 feet, and +10 to damage. He can attack once as a bonus action. If he is controlling mjolnir he can make two attacks.

Gravitational Aura. Each creature within 20 foot radius around Annam feel as if their weight, and the weight of everything they are carrying increases ten fold. Creatures affected are considered heavily encumbered. Their speed drops by 20 feet, and they have disadvantage on ability checks, attack rolls and saving throws that use Strength, Dex or Consititution. In addition, any flying creatures must make a Strength Save DC 24 or fall to the ground. Any creature wearing metal armor in the affected area takes 4d6 damage per round as it crushes them. Any ranged weapon attack fired into or out of the affected area plummets harmlessly to the ground. Creatures in the area of effect holding items must make a strength saving throw DC 24 every round to avoid having that item ripped from their hands. 

Multiattack. Annam can attack three times. 

Spawned Melee Weapon. Melee Weapon Attack: +17 to hit, reach 10 ft., one target. Hit: 28 (3d12 + 9) force damage.

Spawned Ranged Weapon. Ranged Weapon Attack: +12 to hit, range 150/600 ft., one target. Hit: 17 (3d8 + 4) force damage.

Change Shape. Annam magically polymorphs into a humanoid, beast, or giant that has a challenge rating no higher than his own, or back into his true form. He reverts to his true form if he dies. Any equipment he is wearing or carrying is absorbed or borne by the new form (his choice).

In a new form, Annam retains his alignment, hit points, Hit Dice, ability to speak, proficiencies, Legendary Resistance, and Intelligence, Wisdom, and Charisma scores, as well as this action. His statistics and capabilities are otherwise replaced by those of the new form, except any class features or legendary actions of that form.

Annam  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. Annam regains spent legendary actions at the start of its turn.

Attack. Annam makes one attack.

Magnetize Weapon (2 actions). Annam can attempt to rip a weapon that is at least partially made of metal from the hands of another creature within 30 feet. The creature holding the weapon must make a DC 24 strength saving throw or have it ripped from their hands and flying towards him.

Spell (Costs 2 Actions). Annam can cast any at will spell.