Any ideas on what this weird thing is ground on my rock?

[Willbiker]

Hi! what the heck is this!!?

Thanks!

 

[Fishnut]

Dinos

 

[Willbiker]

What the lumpy green thing? I know the brown is, but the green thing looks like a plant of some sort...

 

[Erasmus Crowley]

It could be a majano anemone viewed from the side. Is it round when you look at it from the top-down?

More pics: https://www.melevsreef.com/critter/manjano-anemones

 

[Willbiker]

I think you could be right. Its grown at a remarkable pace and there is another small one next to it on the rock. I wonder how it got in!. Looks like they are a pest so I may have to get rid. Thanks for the feedback