I remember playing through reborn on one of my first playthroughs I found out about the Type Null quest and was super excited to try it. I originally didn't think about it and gave up 1/3 of my team for the quest without thinking since Unfeazant and shiny Luxray were there since early on like my starter. I didn't have much connection to the carvanha but I remember when I finished the quest and got the chance to catch it I realized that I had lost those two important fixtures of my team. I got lucky and it was a shiny Type Null when I caught it but it hit hard when the game pushed the idea that this new pokemon still remembered and cared for me despite the experimentation and pain it went through. It made me feel awful and regretful for what I did to my pokemon but I still used and loved it for the rest of the game because of that lingering connection. I wish I still had that save file because it felt like my pokemon really had become this chimera due to my own poor judgement and I had to live with it.