Basic large slime

slimy Fortitude. If damage reduces the slime to 0 hit points, it must make a Constitution saving throw with a DC of  9+ the damage taken, unless the damage is frozen or from a critical hit. On a success, the slime  to 1 hit point instead.

Slime consumption : when It touches another slime it Consumes it.(add the health of the slime consumed  to the biggest one)

slimy Budding.every time the slime takes damage when its lower than half health , it must make a Constitution saving throw with a DC of 6+ the damage taken if it succeeds it spawns a  medium basic slime with a maximum of two slimes.

Slam. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (3d6 - 3) bludgeoning damage.

Slam. Melee Weapon Attack: +4 to hit, reach 5 ft., one target. Hit: 4 (3d6 - 3) bludgeoning damage.

or

acid absorption: if it is on a square that has biological life it consumes it Hit: 4 (2d6) acid damage. It then heals for half the damage it did