Ok this can’t possibly NOT be a bug. I’ve tested this with the MkVII and VI Heavy swords.
To be clear, we’re talking about the Light attack that immediately follows the Special attack. That Light is different from all others in term of the usual light combo.
A normal Light does 42 or 48 on Flak. The Light that follows up a Special attack does half that : 20 damage.
Doing a Heavy after a special attack deals the usual amount of damage.
If @gpkgpk were here he would probably be able to find out exactly where the typo is in the LUA code .