The Fusion DLC Pack is DLC for Serious Sam HD: The Second Encounter. It was released on February 25th, 2011.
The Fusion DLC Pack lets one play all of the levels, both single player and versus multiplayer, from Serious Sam HD: The First Encounter to Serious Sam HD: The Second Encounter. It is free DLC to those that have Serious Sam HD: The First Encounter. If one originally has just The Second Encounter and purchases The First Encounter, Steam will automatically add the Fusion DLC Pack to their copy of The Second Encounter as soon as they buy TFE for free.
It cannot be purchased separately.
- Currently, the Fusion DLC levels cannot be played online on a dedicated server without messing with server settings. However, they can be played via a peer to peer connection.