boss idea you should make a large-sap-slime or sap-slime-L with the rough description being:
"this sap slime has absorbed so many living things that it has become somewhat intelligent and in the process it has become an ambush predator"
i think this description would fit in with the sap-slime lore. just think about it a mindless sap-slime that absorbed a lot of prey and then getting large enough to gain the smallest resemblance of intelligence would put a bit more lore into sap slimes