Nexus Clash

Last Rite was used on Coron who is level 21 by Katerina Hasheen who is level 25.

As I understand respawn cost should be level/3 so 7 AP. It is showing 8AP.

Under the hood this wasn't actually making it Level/3, it was subtracting a rounded-down Level/6 for either Last Rites or Paragon of Death. There's been some code adjusting to make this more straightforward in the next patch.