HoMM3 HD is a mod (add-on) for the game Heroes of Might and Magic 3.

By the way, are bug reports from version 3.808 still relevant?

Added 3 hours and 42 minutes later
Suggestion: during a siege, if the number of units in the garrison is less than or equal to the number of units the hero can carry, the units from the garrison should be transferred to the hero's army sequentially.