It seems to have been called HardModeManager according to a leftover
context name for loading Aoc/0010/Ecosystem/HardMode.byml
(which also doesn't exist anymore).
Damage stuff seems to be considered game code rather than KingSystem
code based on the function order in the executable and on the fact
that the Damage code uses other components that are known to be
in Game/U-King rather than in KingSystem.