This is a mild remix of the awesome multi-material version of the classic marlin by Cipis.
I found that on that version, the colors go all the way through the fish, so that the adhesion between the color sections is similar to inter-layer adhesion. This causes a weakness in particular in the thin tail area and it's pretty easy to snap the tail along color lines (depending on the materials used).
I used Blender (first-time user - sorry for the very rough job) to join all 4 pieces of the main body (orange) through a central core that provides much higher structural integrity and makes it virtually impossible to snap off the tail.
Aug-2024: Added a second 3mf with all body parts separated (pupils, teeth…) so that more creative color combos can be printed.
Print with 3 perimeters (as per 3mf) for best structural integrity.
The photos shows the happy family (can you tell the original multi-material vs the newer strengthened ones?), a picture of the sliced file showing the orange color with 3 perimeters going through the whole model and finally an example of a snapped tail on the original model.
The author remixed this model.
The main body (orange) was reworked to have a core that ties all 4 parts together.