Cavaliere Angelo is encountered as the level boss of Mission 11 then becomes part of the boss rush in Mission 14 as Mirage Cavaliere.
If cycle fails then Cavaliere will constantly teleport around. Thereofre, it's better to restart the checkpoint to re-do the fight. Unless his HP is one move away from death.
This boss fight is scripted and will go the same way every time.
New Game cycle
New Game+ cycle
As long as Nightmare summon is done correctly along with the DPS check with Griffon's Blockade + Shadow. This fight will be scripted and will go the same way every time.
New Game example
New Game+ example
This cycle depends on DG position. However, it's important for Devil Hunter runners to pause after the inital Guard Break for the 60 FPS change. This because Cavaliere stun lasts longer which allows you to get enough Void Slash hits for the cycle. Therefore, before the last strike hits, change it back to variable.
Mission 11 Void Slash Loop
Mission 14 Mirage cycle