Simple, highly articulated model of the Jellyray from Subnautica!
This one's a good bed adhesion test, as it covers a big part of the build plate. (and pretty much the entire plate for the A1 mini)
Wash your build plate with warm water, dish water and a sponge, if your parts are getting unstuck, your build plate is unclean.

Printed with blue glow-in-the-dark filament.
No supports.
If you find that the links seem stuck, simply use your fingers to free them, you should hear a satisfying crack with each link as it becomes free. If they are fusing and can't be freed, this might indicate over-extrusion issues.