One Digimon with two different levels?

[Yamato-san]

Chimairamon was also originally an Ultimate when he was introduced as the second component of Milleniummon in Anode/Cathode tamer. Ultimate makes indeed sense as it made him a more straightforward counterpart to Mugendramon, although Mugendramon does of course contain more parts of perfect Digimon than Chimairamon does. But then Zero Two came along and... well I guess it would have messed up the escalation of the story's stakes if they had defeated an Ultimate in the first half of the Series.

Interesting to hear that it was an Ultimate in Anode/Cathode, but that wasn't where it was introduced. Chimeramon was first implemented in Digital Monster Ver. Wonderswan, where it was a Perfect.