My Top Ten Strongest DP Character list (In terms of standard raw power), so this doesn't include moves that would count as buff (Ghostly Wail)
1. Vlad Plasmius (New Emotional Drive) - Completely overpowered Dark Danny (Clockwork Overshadowed) after attaining his new drive.
2. Dark Danny (Clockwork Overshadowed) - Knocked out Danny Phantom (New Emotional Drive), Vlad Plasmius (Pre Emotional Drive), and the strongest ghost hunters with one explosion wave despite Danny putting up an ecto shield.
3. Danny Phantom (New Emotional Drive) / Ghost Hunters (with weaponry) - Danny with his new drive could harm Dark Danny even after he overshadowed Clockwork although is overall weaker. The same for the Ghost Hunters like Valerie Gray and the Fentons, their weapons can harm him just not do serious damage.
4. Dark Danny (Pre-Clockwork Overshadow) - Stated that no one could stop him (at that time), which would include Pariah Dark (Crown and Ring), who he knows exist.
5. Future Fright Knight - Knocked out Future Valerie briefly who can somewhat survive attacks from Dark Danny although not many.
6. Future Valerie - The only person in the future timeline that could stand up to Dark Danny and her weapons could knock back Dark Danny and he opted to dodge them.
7. Ancient Ghosts (Together) - Their power together was just enough to knock out Pariah Dark (Crown and Ring). However Individually their weaker to an unknown extent.
8. Pariah Dark (Crown and Ring) - The strongest ghost (Individually and not including the future timeline and the Graphic Novel events that come later). Even without the Crown and Ring), practically every ghost fears him, and even Danny and Vlad during the Graphic Novel events (Pre Emotional Drive) both admitted that if Pariah got out, they'd be doomed.
9. Danny Phantom (Season 2/Exoskeleton) - Comparable to Pariah Dark (Crown and Ring) as he could harm him to some degree, although weaker.
10. Pariah Dark (Base) - Stated to be the only ghost with enough power to handle the of the Crown of Fire and Ring of Rage (Dark Danny doesn't exist at this time), making him the strongest ghost individual. Even without the Crown and Ring), practically every ghost fears him, and even Danny and Vlad during the Graphic Novel events (Both Pre Emotional Drive) both admitted that if Pariah got out, they'd be doomed.