Oob

Trained by Perdan himself, Oob is an exemplar of brutal, formless efficiency. Use your abilities as a slimefolk to perfect the art of espionage and elimination. Ingrained with military discipline, this path is one of goals and actions. Learn their secrets and then seal their lips. By force or by finesse, when Oob is set in motion, the outcome is preordained. 

Slimy Tactics

Starting at 3rd level, you begin to take control of your Ooze-like body; you have learned how to use your skills to gain the upper hand on a target. Your ability to manipulate your form is represented by Ooze Points. You have six Ooze points, each of which may be used to facilitate your slimy tactics, which are detailed below. 2 Ooze Points are restored per short rest. 

Brutality. When you successfully roll to hit a sneak attack, if you roll above 18 (cumulative), you may spend 2 Ooze Points in order to finish your attack with a devastating, hydraulically pressurised kick. The target cannot make opportunity attacks until the end of their next turn.

Reversal. When creature fails a melee attack roll against you, you may spend 2 Ooze Points in order to use your engulfing form to make a grapple of opportunity against that creature. If they fail, they are pulled towards you if they are more than 5ft away. 

Guerilla. When you score a hit on a surprised creature, you may spend 2 Ooze Points in order to slink forward and make an extra attack on a separate, surprised creature within 10ft. Moving to hit this target counts against your movement speed for the turn.

Slither. When you make a movement that requires a stealth check, you can get advantage on your roll by spending 2 Ooze Point, manipulating your body to quieten your stride.

Among Us

At 9th level, you gain the ability to mould your form and inhabit any (superficially complete) corpse to disguise yourself and infiltrate hostile territory.

If the brain of the corpse is intact, you gain the ability to unerringly mimic its speech, writing, and behaviour in life. Your ruse is indiscernible to the casual observer. If a wary creature suspects something is amiss, you have advantage on any Charisma (Deception) check you make to avoid detection.

If the brain of the corpse is not intact, your ruse will still be undetectable to casual observers, but you will not be able to roll with advantage to avoid detection under closer scrutiny.

The worn corpse grants +2 AC and 1 temporary hit point, but your disguise is ruined if you take any damage, regardless of armour worn by the corpse. The disguise is also ruined as soon as you make any melee attack. 

Flow

At 13th level, you have become more adept at controlling your Ooze-like body. You gain more abilities and 2 more Ooze points. 

Leverage. When you make a grapple, you can spend 2 Ooze Points to entangle your target with alarming agility and finesse. In doing so, you can use your Dexterity (Acrobatics) instead of Strength (Athletics) to make your contested grapple roll. 

Pressure. On your turn, you can spend 2 Ooze points to forgo an action to build pressure within your body. On your next turn, you may add 1d10 force damage to your attack. 

Liquify. When an enemy successfully hits you, you can spend 4 Ooze Points to liquify your body at the moment and site of impact which cuts your damage taken in half. 

Orders

At 17th level, your prowess as an assassin can now benefit your allies. After you make an attack against a creature, you are able to identify its vitals and weaknesses and notify your comrades. Subsequent attacks from two allies on the targeted creature can now score critical damage on an 18, 19, or 20 (natural) for the next turn.