Basically maybe a big version of the purple plant or a combination of all of them and they can in their stage 2 make those thorn grass pop up where ever an attack hits the floor. And to damage it more you hit the head of the plant. And during stage 2 the heads can be hidden by closing its petals where they cannot be damaged. They can also spawn those ceiling plant enemies and floor ones. Maybe the red flower can shoot the plants on the wall and you have to take it out to stop enemies from spawning. Maybe called the corrupted tree
#New plant boss
fervent rapids
polar sluice
just add the old killer plant boss