
However, on discovering this, we decided to keep them as they were more fun (and random - keeping in with BB).

The rules we used were this. The apothercary can be used to make yor opponent re-roll either an 2D6 injury roll or the D6 roll for serious injuries. he 2nd roll must be taken even if it is worse (or better, depending on your point of view).
Sod's law - In the league if your oppo rolled a 10+, a re-roll would always come up 10+ again.
