Or.
Any amount of people combine and their combined health is the number of them * 100.
They still retain their collision boxes, but each of them has the amount of health as the whole does. When you manage to kill one on the end, the health then goes down tho the amount of people still in the link * 100. When you kill one in the middle, then the two ends split and the newly created ends have the total health of each group, in the same manner as discussed above.
Once all of the pieces are killed off then you win.
BAM!!!
New Gamemode.