Easy to find, eg

https://oceaninfo.com/list/poisonous-ocean-animals/

https://www.livescience.com/animals/13-of-the-most-venomous-sea-creatures-on-earth

https://oceanconservancy.org/blog/2021/10/06/5-venomous-ocean-animals/

etc. there you’ll finde some more of this cute little animals. For more, you probably have one or more search engines in your browser (see instructions)