Is Judaism a Team or Individual Sport? Part 1

To what extent is the enterprise of mitzvot an individual or team "sport"? Is there a notion of a “sacrifice” in the observance of mitzvot? What if I can considerably improve someone else’s religious record if only I take a small hit to my own? Am I permitted to violate a prohibition so long as doing so will prevent another Jew from committing an even graver trespass? (5776)