Personally, Scourge if he counts! He had such a strong introduction and his parallel to Firestar was brilliant! Honestly he was very under utilized and I would’ve loved to see him come back as a dark forest (or kitty pet/rogue equivalent) cat. Like leading up, Tigerstar was the main villain of several books only to be murdered nine times from one hit by this tiny apprentice sized cat, crazy! It stuck with me the most.
Also I always thought his most apparent parallel with Firestar (their collars) was so fascinating! Like Rusty, after his fight with Longtail, loses his collar signaling his leaving behind his old life and into a new one as a warrior! While Tiny after his ‘fight’ (getting attacked) by Tigerpaw,
didn’t lose his collar signaling his inability to leave the life he had previously (cold, abusive, sad) and he embraced it. Until Firestar killed Scourge and ripped Scourge’s collar off in the process I think it was almost like freeing Scourge. Also interesting is the fire association with Firestar and the ice association with Scourge!
Anyways….Scourge
I like him quite a bit.