Jazz Jackrabbit 2 Plus (JJ2+) adds countless features and bug fixes to both Single Player and Multiplayer gameplay within JJ2, and is used almost universally by most serious players. It has much better network code than the original game, adding console commands to online games, fixing most major game-crashing errors and connection problems, allowing permitted clients to log in as "remote administrators" in someone else's server and control the gameplay, and adding several new multiplayer gamemodes. It additionally fixes or enhances many of the events in the game, and allows level designers far more power than in regular JJ2 through the addition of an easy-to-use scripting language. JJ2+ takes everything great about JJ2 and adds so much more on top of it; it is truly a must-download. JJ2+ is distributed under the MIT license.
JJ2+ adds many improvements to online gameplay, including several HUD-related details pictured here. All players in team-based games have their names rendered entirely in blue or red depending on their team. Flag-holders in Capture the Flag receive orange stars next to their names, so that all players know whom to target. The player list also keeps track of how many times each player has killed another player or been killed themselves, for recording or simply for bragging rights. The game can be stopped or started at the whim of the server or remote administrators, and while the game is stopped, no fighting can take place. The Console receives various commands from the server/remote admins and announces their effects on gameplay.