This skill is a Special Rule that is only available to specific Star Players. Please visit this page to find a list of current and past Blood Bowl Star Players.
The BallistaOnce per game, if Morg fails the Passing Ability test when making a Pass action or a Throw Team-mate action, you may re-roll the D6.
Most players tend to just use Morg to take advantage of the obscene Mighty Blow (+2) ability. This means blocking or blitzing with him on pretty much every turn. If you’re doing that then he isn’t really ever to be likely performing a pass which renders this special rule a little redundant and nothing to get excited about.
I can see some situations where you might be trying a one turn touchdown attempt by using Throw Team-mate if you’re using him on an applicable team. Even then you still might be better off hitting with Morg and using the normal Big Guy on the team for the Throw Team-mate. Sure Morg is probably a bit better at throwing players but he’s also much better at injuring opponents as well.