Danny and phantom end up split- BUT- it wasn't on purpose and it wasn't the ghost catcher this time.
Danny just woke up one day feeling hollow. He's missing his core, his powers won't work, he can't sence ghosts, it's like he's fully human again! Exept, his ghost core was keeping him alive, for the most part. Now he's having near constant heart palpitations, his muscles contract up painfully sometimes and the longer he's without his ghost, the worse it gets. He needs to find out and get his ghost back. Quick! He's not sure how long he'll last without it...
Meanwhile, in the ghost zone, phantom wakes up. Given dannys ghost is only about two years old, at this point, he's basically a confused baby. His names phantom...and...he needs to find the portal. He lost something important and he needs to find it! What did he loose...? Ummm, he's not sure, actually, but it feels really really important. Maybe it will fix this empty feeling he has. Like he's missing his core, did he loose it? No, he has it, so...what's supposed to be there?
Now the two have to find eatchother with Danny dieing and phantom destabilising, though he dosn't know that's what those weird jolts are.