Summary
Merida, Hiccup, Jack Frost, and Rapunzel are selected by S.H.I.E.L.D. to form a group known as the Big Four(aka Avengers). Will they defeat Pitch? Will they deal with Jacks immaturity long enough to do so? Will I manage to finish a story for once on my life? Never done a fanfic before, so rated to be cautious.