Multiplayer/Co-Op & Frictional Games? NO!!!

[Apjjm]

It is theoretically possible*, it would also be far too difficult to achieve (Lol @ even thinking about doing it in assembler). For example, just syncing up player models would be require additions to the game code - then what happens if the players are in different levels? Run a "server" which communicates placements but the players are in two independent worlds but can see each other if they are in the same map, yet syncs the monsters and tweaks the path-finding to weight multiple target nodes? Good look getting that working without the source code to the game, hell, good luck getting it working with the source code of the game, because it would take a huge amount of work.

*But not humanly achievable or feasible.