Teal Slime Family

The Teal Slime Family is a group of similar monsters, composed of the Teal Slime, Giant Teal Slime, and the King Teal Slime. Although they are used elsewhere, they are mostly spawned by Slimelius's Slime Slices passive ability. All of the teal slimes can fuse into the next one by combining in groups of 5. 5 Teal Slimes fuse together to make a Giant Teal Slime, and if you're unlucky enough, 5 Giant Teal Slimes can fuse together to make the dangerous King Teal Slime.

Teal Slime
Medium Slime Attacks are essentially that of an ochre jelly other than stats. If 5 or more are within 10 feet of each other, they will combine into a Giant Teal Slime (see below). All teal slimes are chaotic neutral.

Giant Teal Slime
Large Slime Essentially a stronger Teal Slime (see above). If 5 or more are within 15 feet of each other, they will combine into King Teal Slime (see below).

King Teal Slime
Huge Slime

KTS can only appear if the battle against Slimelius is being waged by a team of 3+. If only one or two are fighting, the Giant Teal Slimes will not fuse and KTS will not appear. THIS is why you shouldn’t let the Teal Slimes congregate too much. The presence of a King Slime will change the alignment of all Teal Slimes not including Slimelius into Chaotic Evil, and the King Slime will command its troops in order to make the optimal battle plan. King TS is arguably overpowered, however, he is meant more to act as a punishment for letting the Teal Slimes take over. Doing the math, at the most, Slimelius will spawn a maximum of 36 Teal Slimes (not including legendary actions), and it takes 25 of them to combine into a King. This means that you only have to kill 12 Teal Slimes at the most to prevent KS from ever spawning, so if you end up dealing with a KS during the Slimelius fight you have seriously done something wrong.

Action:

Jump - KS jumps up 25 feet into the air, and then lands down 15 feet away from the beginning location and deals 1d20 + 15 bludgeoning damage to anything hit by KS.