Spellcasting: being literally beyond gods, it is able to cast spells not even gods are capable of, in other words,  he can use 10th level spells, while gods can only use level 9.5, it has these spells prepared:

Cantrips: Eldritch blast, Minor illusion, Thunderclap

Level 1 spell: Hex, Thunderwave, witch bolt 

Level 2 spells: Cloud of daggers, Hold person, invisibility, mirror image

Level 3 spells: Counter spell, Vampiric touch, summon lesser demon

Level 4 spells: Banishment, Diemention door, Summon greater demon

Level 5 spells: Far step, Infernal calling

Level 6 spells: Circle of death, Create undead, Soul cage

Level 7 spells: Plain shift(teleports the entire area to a different plane), Finger of death

Level 8 spells: Maddening darkness

Level 9 spells: Blade of disaster, Imprisonment 

Level 9.5 spells: Summon demi-God, power word deletion (basically power word kill but instead of 100 hp or less, it's for 200 hp or less,they also cant be revived if killed in this way because, well, the name says the reason perfectly), Time stop 

Level 10 spells: /kill @e(basically just power word deletion but instead of only using it on one person, they use it on everyone in a 5 ft radius AND the target), Summon deity 

Challenge Override - Vjangesh is actually challenge rating 100, meaning he gives 10 million experience apon death, he only gives this experience after you kill all of his different phases(search "Vjangesh" on the homebrew thing for the other phases, note that some phases may not be posted at the time your reading this)

It's just the earth lord from the terraria fan wiki, but just in case you don't know who that is(and because I want to have more too do), I will still be saying the attacks, oh, and since he also looks like earth lord except hellish, he still has to have the mechanic of multiple body parts to attack, and because of this, the 30000 is that per body part, and there is 4 body parts(not counting the respawning nonnessasary to kill parts), ok, now we can actually go on to the attacks

Hand/head eye attacks: the hand eye open every 2 turns, while the the head eye opens every 3 turns once it opens, it can use the following attacks:

Eye laser: shoots a small laser that is small enough to be dodged, however, due to its speed, it requires a DC of 25, if you fail to dodge it tho, it deals 250 damage, as well as every 1 in 5 chance to stun the target for 5 turns

Health leach: the eyes can summon these health leach clots, they have 1000 life, and summons health leach`s and they have 500 hp and they`re attack is listed below:

Hp steal: while only dealing 5 damage, every time they hit a player they heal one of the body parts of the main boss by 5000 hit points

Now back to the eye attacks:

Hellish deathray: Instant kill, oh, and that's a attack that a attack that only the head eye can use, and also the final eye attack

Now be careful, because for every eye you defeat, it summons a released eye, and they have their own attacks, they are said below:

Phantom eye: summons a phantom version of its self, this phantom just acts like a beholder except immortal but disappears after 5 turns(witch by the way the released eye I also immortal but only disappears when the phase ends), oh, and also the phantoms can shoot basically just eye lasers but half damage

Hellish laser: hellish deathray but not an instant kill, but instead it deals 500 damage

Eye laser:literally just the eye laser from earlier except without the "dealing half damage" thing

So yeah, good luck, oh and btw we still aren`t done, we still have the attacks that didnt`t fit any section

Tentacle grab: a tentacle comes out of its mouth and drags you to the mouth

Eat victim: this attack wasn`t in the original thing I got the attacks from but its basically just the tarrasque version of this attack except more damage and its mouth also isn`t to small to use on a said tarrasque, oh and the damage dealt by the attack is given to the head eye to itself with, and if the head eye is destroyed by then it just revives the eye and removes its corresponding released eye from existence, it then sets it current hp to however much damage dealt to the target

Cool but there's also phase 1.5, you see, when the core is destroyed, it revives with half hp, just like it does in the og if your in expert mode, although it doesn`t do what the og did, for instead of just reviving with doing the same attacks and stuff, instead, it exists it containment, becoming a new enemy moving around, just like the released eyes, however, unlike those eyes, it does not become immortal, and you must kill it to end the phass, thus why it's called phase 1.5, although remember the main body can still attack, oh and the eat victim attack can no longer revive the head

Now, the ascended core`s are as follows:

Dash: dash`s at his target, dealing 150 damage, if you fail a DC 25 check, it makes you fall over, stunning you for 3 turns

Invisabilty: goes invisible, one turn later and now they are trying to crush you, and unless you have true sight, or make a DC 20 perception check, is impossible to dodge, witch, in the case you gained the ability to dodge it, you must make a DC 15 athletics check, if you fail or don't have the ability to dodge it, you take 250 damage, as well as stunning you for 5 turns

Spike floor: summons 3 spikes from the ground, each targeting a different player, dealing 75 damage each

Beams of energy: rolls a d20, if it gets a 1-10, it shoots 16 beams of energy, but 11-19, it's 17 of them and fo a 20, it shoots 18 of them, and they each deal 50 damage

Heal self: 8 balls of energy surround the core, they all then go into the core, healing them by 500 life

And that's it, that's all the attacks, good luck to any players you this creature in your campaign of

It has infinite legendary action points because its beyond a God and stuff, it has 3 different types of legendary actions, they are said below:

Spellcasting: uses one of his many spells

Tentacle grab: uses the tentacle from its mouth

Hellish deathray(if the eye for this ability has become a relased eye, thus ability is replaced with the phantom eye ability)

It has 3 mythic action points because yes,

Spellcasting - Vjangesh casts one of his spells

Tentacle grab: Vjangesh uses the Tentacles from his mouth