Sacrificial Attack

In keeping with the theme of the name of the tournament, today's Solstice Sacrifice youth chess tournament has a problem solving contest concerning a sacrificial attack. In this case, all six positions are theoretical positions that might have occurred, but did not, in Mayet -- Anderssen, 1851.

Black has a winning sequence from each position.

1.

2.

3.

4.

5.

6.