Hello,
The new implementation of Imperius maintaining marks on targets airborne during Wrath does not work correctly. If a mark is applied, that mark will always be reapplied every time Wrath of Angiris hits an enemy hero. This effectively means Imperius only needs to hit a hero with 3 marks once. After that, he will always get max damage upon landing when casting Wrath, and the target will always have 3 marks on them upon landing (even if they started with 0).