Shayde the Devastator (5e Creature)
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Huge undead, neutral evil
Saving Throws Str +46, Dex +38, Con +46, Int +46, Wis +42, Cha +46
Scourge Resilience (Mythic Trait, recharges after a short or long rest). When Shayde is reduced to 0 hit points, he dosen't die or fall unconscious. Instead, he regains 10000 hit points and up to 500 spent spell slots, and then can make two attacks with his crushing claw or arcane longbow against the creature that reduced him to 0 hit points, or make one attack with the staff of shayde against the creature.
Mythic Spellcasting. Shayde's spellcasting ability is Intelligence (spell save DC 54, +46 to hit with spell attacks). He can use his 1,143 total spell slots for any spell, although he can only use 102 on spells of 25th level or higher.
Legendary Resistance (22/day). If Shayde fails a saving throw, he can choose to succeed instead.
Damage Threshold.' Shayde has a damage threshold of 60.
Relentless (3/rest). If Shayde takes 341 damage or less that would reduce him to 0 hit points, he is reduced to 50 hit points instead.
Aura. Shayde can have one of these effects in place. He can switch auras as a bonus action:
Mythic Necrotic. Necrotic damage dealt by Shayde is so powerful that it ignores resistance, and treats immunity as resistance.
Regeneration. Shayde regins 150 hit points at the start if his turn. If he takes at least 130 radiant damage, this trait dosen't function at the start of his next turn. Shayde can only die if he starts his turn with 0 hit points and does not regenerate.
Reactive. Shayde can take up to 4 reactions each round. He can't use two reactions at once.
Inevitably Powerful. Shayde is immune to any effects that reduce his ability scores, steal spell slots, or reduce his hit point maximum. Also, Shayde has a damage threshold of 50, and all his attacks are magical.
Lore Master. Any creature that encounters Shayde must start it's turn with a DC 54 Intelligence (Arcana) check. On a fail, the creature takes 42 (12d6) psychic damage, and is stunned until the start of it's next turn.
Arcane Ability. Spells cast by Shayde ignore resistance to necrotic damage, but not immunity to necrotic damage. Also, if Shayde deals 1000 or more necrotic damage with a spell, resistance does not fully apply, but half-applies if the target has necrotic resistance, meaning that the creature takes three quarters of the original damage, not half.
Multiattack. Shayde casts up to three spells of 20th level of lower, or any one spell. He then makes two claw attacks or arcane longbow attacks or one of each, two attacks with the staff of shayde, and uses Necrotic Breath if he can.
Crushing Claw. Melee Weapon Attack: +46 to hit, reach 10 ft., one target. Hit: 306 (44d12 + 20) bludgeoning damage plus 90 (20d8) necrotic damage, and the target must make a DC 54 Strength saving throw. On a failure, the target goes flat and becomes half as tall and twice as wide, reducing it's size by one, for 1 minute.
Arcane Longbow. Ranged Weapon Attack: +46 to hit, range infinity (assuming that Shayde can see the target, and has a direct line to it), one target. Hit: 290 (60d8 + 20) piercing damage plus 99 (22d8) necrotic damage, and the target must succeed on a DC 54 Constitution saving throw or take 7 (2d6) necrotic damage at the start of it's next turn, and be stunned for that turn.
Staff of Shayde. Melee Weapon Attack: +46 to hit, reach 10 ft., one target. Hit: 75 (10d10 + 20) bludgeoning damage plus another 75 (10d10 + 20) bludgeoning damage, plus 880 (160d10) necrotic damage. A creature hit by the staff of shayde must succeed on a DC 54 Constitution saving throw or be paralyzed for 1 minute. While in this state, a creature automatically fails all saving throws and ability checks. If a creature takes a critical hit from this attack while paralyzed from the staff of shayde, it must toll a d20 ad roll a 15 or higher to succeed (13 or higher if it has Constitution of 31 or higher). On a fail, the creature drops to 0 hit points. Also, the staff of shayde causes any celestial or devil hit by it to make a DC 52 Constitution saving throw. On a fail, the creature dies if it has 100 or fewer HP. Otherwise, it's hit point total becomes 100.
Empowered Spell (recharge 5-6). Shayde casts any spell, using a spell slot. The spell has it's normal effect, but if a target fails a saving throw against the spell or the spell attack hits it, the creature takes an extra 110 (20d10) necrotic damage, and is stunned until freed by the greater restoration spell or similar magic cast at 9th level or higher.
Summon Megoi (recharge 5-6). Shayde chooses what to summon and performs a magical summoning. He can use one of the following summoning options:
Necrotic Breath (recharge 5-6). Shayde exhales energy in a 400 foot cone. Each creature in that area takes 1100 (200d10) necrotic damage, or half as much damage with a successful DC 54 Constitution save. This effect counts as magical and ignores resistance, as in in the Arcane Ability trait above.
Doom (recharge 6). Shayde chooses a creature within 300 feet and puts a doom counter on it. The doom counter starts at 9. Every round on the creature's turn, it takes 7 (2d6) necrotic damage, and the doom counter drops by 1. When it gets to 0, the creature makes a DC 54 Constitution saving throw. On a failure, the creature drops to 0 hit points. On a natural 1, the creature dies and can't be restored to life. On a success, the creature takes 660 (120d10) necrotic damage.
Magic Drain (recharge 1d8). Shayde chooses a spellcaster within 300 feet and puts a magic drain on it, which deals 110 (20d10) necrotic damage to that creature. While under the effects of a magic drain, a creature makes a choice every round at the start of it's turn: Either it takes 220 (40d10) necrotic damage and is stunned until the start of it's next turn, or it loses a spell slot of a random level that it can cast. It can't choose the damage option two turns in a row. A magic drain lasts 1 minute, or until Shayde chooses to end it.
Forbid. In response to a creature trying to target Shayde with a spell while within 500 feet of Shayde, Shayde can force a DC 54 save using the creature's spellcasting ability. On a fail, the creature fails to cast the spell, takes 99 (18d10) psychic damage, and fails to cast the spell, wasting the spell slot. Shayde can only use this reaction once per round.
Flatten. In response to being hit with a melee attack that bypasses Shayde's damage threshold, Shayde can make one claw attack with advantage against the attacker.
The Shayde can take 22 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. The Shayde regains spent legendary actions at the start of its turn.
Spell (Costs up to 20 Actions). Shayde casts a spell of 20th level or lower, expending a spell slot, and using one legendary action per level of the spell.
'Please see this page for a justification (in progress).
Shayde is the All-Powerful Archlich, the Scourge of Life, and the Devastator. He is rumored to be the being who created the megoi.
Scourge Strength. Shayde is an 18-foot skeleton with parts replaced with metal, clad in a billowing black cloak, and with two enormous Arcanetarakk claws that are strong enough to crush an adveturer flat. But Shayde's main power is his spells, which make him almost unstoppable.
Staff of Death. Shayde's staff is a 9-foot metal double-ended rod, with almost unimaginable power.
Shayde as a mythic encounter. Shayde presents a challenge even more powerful than a normal CR99 creature presents. Award a party 11 million XP for defeating Shayde after he uses Scourge Resilience. Read the following text when Shayde uses his mythic trait: