Arms Law page 18,
Large Creature Critical Strikes ? Only critical strikes of severity
?B?, ?C?, ?D?, or ?E? affect large creatures (i.e., ?A? severity criticals are
ignored). A high open-ended roll is made and cross-indexed with
the weapon type on the Large Creature Critical Strike Table. The
result obtained is applied immediately. Note that the severity of
the critical strike is irrelevant, except that it must be of ?B? severity
or higher. This reflects the fact that such creatures present such a
large target that they are much more difficult to seriously hurt.
Super-Large Creature Critical Strikes ? Only critical strikes of
severity ?D? or ?E? affect super-large creatures (i.e., ?A?, ?B?, and ?C?
severity criticals are ignored). A high open-ended roll is made
and cross-indexed with the weapon type on the Super-Large
Creature Critical Strike Table. The result obtained is applied
immediately