Serious Sam XBOX is a mod for Serious Sam: The Second Encounter that transforms the game into the Xbox version. It includes a new HUD, a lives system, a combo multiplier, a jetpack, new weapon models, and a completely new "Defend" mode. New enemy types have been added, appearing in both single-player and multiplayer modes. Maps from The First Encounter are also supported. The mod expands editor capabilities with new objects (Entities) for creating vehicles, turrets, and scripted systems, allowing for the creation of new custom levels.
Mod Features:
Defend Mode:
A new multiplayer mode where you fight alongside other players on round-based maps with specific objectives (though these usually involve either staying alive or killing a specific enemy). After each round, enemy strength adjusts to the players' skill level based on their win/loss ratio. On some maps, a player may spawn as the "Kingpin." You can recognize them by their golden glowing skin. If the Kingpin dies, the players lose, so make sure they survive. There is also a (test) map featuring spacefighter vehicles; it is primarily intended for Deathmatch gameplay, but this functionality is still being refined. For now, you can simply battle each other without any limitations.
New Enemies:
Several new enemies have been added to the game. They appear randomly in single-player/co-op as well as in Defend Mode.
Jetpack:
This mod features a jetpack. Control it using the movement keys and the jump key. If you want to use it in single-player, you can obtain it using the new "please jetpack" cheat code.
New Multiplayer Options:
When hosting a game, several new parameters are available in the game settings. These are related to the lives system and allow you to fine-tune the difficulty.
New Effects:
Thanks to asko there's now a very cool motion blur effect when you collect Serious Speed powerup. If you don't like it, turn it off in Advanced Rendering options.
Editing:
Many new and powerful entities have been created, allowing for a form of map scripting (property changers, conditions, displays, button controllers, etc.). These allow you to create various new features such as vehicles (albeit without physics), turrets, random enemy spawning, and more. You can find the documentation for these in the entities.txt file.