seastars, or starfish may be poisonous
bacteria
they move by the bottom of their arms
Seastars are invertebrates.
squid and seastars
No -- starfish or seastars are echinoderms and as such are invertebrates. -- no spines.
seagulls, crabs, some fish, seastars
they are in kingdom animalia but it doesn't have a backbone
The seastars don't have houses they live on the coral.
Clams, oysters, and small fish, because they are carnivorous.
Seastars are not recommended as pets for the average person as they have specific care requirements and can be challenging to keep in a home aquarium. They also have specialized feeding habits and can be delicate to changes in water conditions, which can make them difficult to care for in a home setting.
Some types of starfish eat other smaller species of starfish, if that was what you were getting at.