Flight is a common keyword mechanic found in all shards, but primarily in Sapphire, Diamond, and Blood. Troops with Flight can only be blocked by other troops with Flight, or troops with Skyguard.
The Angel could be blocked by either of these two troops. It could be blocked by the Sterling Skywatcher because it has Skyguard, or also by the Spearcliff Cloud Knight because it also has Flight.
- If a troop with Flight blocks a troop with Flight and then somehow loses Flight, the attacking troop is still considered blocked and both troops will deal damage to each other.