Animation is shared between all instances of a scene (unwanted)

Hey, sorry if this is a common thing that has been asked before, but my Google-Fu has failed me on this issue and if there's a duplicate I haven't found it.

Context:
I'm playing around with creating enemies, which currently only take damage and die. I wanted them to flash red upon damage, so I gave the enemy scene an AnimationPlayer and an Animation that just changes the albedo colour of the material the enemy uses (single material on a simple Meshinstance).

My problem:
Everything works as expected, except that whenever I hit one enemy, every enemy will flash red, instead of just the enemy hit (video: https://imgur.com/a/KUBZV6C).
My attempted solution was to edit the enemy scene, select the MeshInstace, its Mesh, go to the material and right click -> "make unique". I've also tried telling the AnimationPlayer in the enemy scene to make all sub-recources unique, since even with supposedly unique materials the enemies still all flash as if sharing the same AnimationPlayer. Problem persists.
I haven't done much in Godot before, so I'm sorry if this is really basic and uninteresting.