I’d like to create an effect similar to 2 death animations that exist in Crash Bandicoot 3.
In one of them, Crash is disintegrated: all the triangle faces get separated and fly apart. A similar triangle separation is seen when he dies from fire, the triangles fall separately.
The second is a simple separation of the legs and torso. One enemy that exists in the 1st stage can cut Crash in half, which will cause the torso to stay in place while the legs walk away.
Crash uses a set of customized death mesh and animations that are swapped with the “main” player character at the time of death.
Using the separation example because it’s easier. When the player dies, the game will check what killed the player, hide the “normal” crash model, select and display the unique “death crash” model, then play the death animation associated with it. That version of crash already has the character split into two halves and is only created to operate with that animation.
A good starting point would be looking into techniques for breakable objects like crates or pots.
Edit- this may be a bit easier to visualize, the deaths where crash turns into an Angel. Again the primary model is removed from view, a new model with crash translucent and with wings is made visible, and the animation of him floating upwards is played.
Edit2- and I guess to answer your question, you wouldn’t do this entirely in Godot. You’d want to prep your alternative models and animations in your 3d tool of choice, then import them into the project. Godot would basically just be used to swap the models at the appropriate time.