When a damage reduction effect is in play like Blue Storm, the opener displays the remaining damage as opposed to its actual damage. For example, if Grave opens with a throw during his opponent's Blue Storm, his throw would display that it has 3 damage instead of 7 (because the Storm counts the 10 damage threshold, subtracts the throw's 7 damage, and then displays the remaining dealable 3 on the throw opener rather than on any followup combo cards.
#Card damage display on damage reduction effects
dawn dagger
distant berry
Confirmed, I'll fix this