There has been a flood of co-op runs come in this month and some of them are absolute gems. Co-op runs usually come in three flavors. First, where the second player follows (cabooses) the faster runner. Second, where both players contribute equally. Third, where the players coordinate their efforts to run the level faster than is possible for a single runner. Thankfully, most of these runs are in the second and third categories.
Riptor and Warlord:
Sweep The Pillar Of Autumn Easy 4:18, Normal 4:27, Heroic 4:28 and Legendary 5:27