Amorphous. The ooze can move through a space as narrow as 1 inch with with out squeezing. Anything smaller is treated as rough terrain. 

Arcane Reconstruction. The ooze when with in 15 feet of any spellcaster or target that has spell slots, that caster must make a Constitution Saving throw DC 22, If they fail the save the Ooze uses one of their Highest spell Slots available, and uses it to heal it self 1 D6 for each spell slot used. All spell slots that are taken in this fashion are expended to the caster. Recharge: 4 - 6 

Chaotic Defenses. When attacked by a spell of any sort one of the follow three effects happen, the affect is at random and must be rolled. The effect can be doubled if the Ooze rolls a 6 on a D6, otherwise it goes off as it is stated. 

1-2: Silencing Echo - When hit with a spell the caster that used a spell against it must make a DC 15 Wisdom save or become silenced and cut off from the weave until the end of your next turn. If this effected is doubled they are cut off for 2 rounds, no spells can be cast during the time of silence. 

3-4: Arcane Haste - When hit with a spell the Ooze gains the effects of Haste until the end of his next turn. If the spell that is cast is a Lightning Spell Ignore all rolls for random affects and choose this one, when this happens the ooze Ignores the negative affects of the Haste. There is no additional affect that is gained from a 6 being rolled for this ability.

5 -6: Arcane Rebuke -  When hit with a spell, the spell deals half damage to the ooze and returns the full damage back on the caster. The Damage is considered Force damage. If the effect is doubled in due part to a 6 being rolled add an additional 1D4 +5 per a spell slot used on the attack spell. 

Dispelling Vulnerability. If the Ooze is the target of a dispel magic, it takes it takes damage equal to 1D10 x the spell slot used. 

Magic Immunity. All spells of 2nd level and Lower the ooze is immune to, any spells of 5th and lower the ooze has resistance, all other spell levels he gains Advantage on all saving throws. 

Multiattack. The ooze makes two attacks with its pseudopod attack

Pseudopod. Melee Weapon Attack: +8 to hit, reach 10 ft., One target. Hit: 16 (2d6 + 4) Bludgeoning damage, 10 (3D6) Acid Damage 

Engulf. The ooze moves up to its speed. While doing so, it can enter Huge or smaller creatures' spaces. Whenever the ooze enters a creature's space, the creature must make a DC 15 Dexterity saving throw.
On a successful save, the creature can choose to be pushed 5 feet back or to the side of the ooze. A creature that chooses not to be pushed suffers the consequences of a failed saving throw. On a failed save, the ooze enters the creature's space, and the creature takes 10 (3d6) acid damage and is engulfed. The engulfed creature can't breathe, is restrained, and takes 21 (6d6) acid damage at the start of each of the ooze's turns. When the ooze moves, the engulfed creature moves with it. An engulfed creature can try to escape by taking an action to make a DC 15 Strength check. On a success, the creature escapes and enters a space of its choice within 5 feet of the ooze. While in the ooze if the target has any unused spell slots available, each round, the Ooze gains the benefits of Arcane Reconstruction despite weather or not the Recharge is up or not. 

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Legendary Action Name (Costs # Actions). Enter the description for your legendary action.