Blood Bowl

To start, begin a new campaign and choose Skaven. Make sure it's on easy, blitz. The real time will make it incredibly easy! You can also choose a one of match if you choose.

Make sure to play against a squishy team. The Goblins, wood elves, or another Skaven will make it easy and prevent all your blockers from being mauled!

Once play begins simply enter concentration mode to focus everyone on the balk carrier while running a gutter runner up to the endzone. Once you have the ball throw it toasted your gutterrunner. Even if the pass misses, in blitz it's no turnover, just scoop it up and run it in!

Alternately you can keep the gutterrunner near the chaos and scoop up the scattered ball and dash to the endzone. Against most teams gutterrunners can simply dodge their way past would be defenders, simply enter concentration mode and select the endzone to keep your ball carrier focused on the prize!

Ta-da achievement unlocked. Using this method I beat a wood elf team 15-2! You can also unlock the SP Cheeves as well.