The major improvements of pb4, compared to 1.3pb3 are:

    * More features, including weapon linking, thumpers, and variable gravity DM maps
    * Increased vista compatability, audio works in WINE
    * Many more modder features, such as 60-char ODF names, inheritance, tons of new tuning values, etc
    * Performance optimizations
    * Fewer resyncs, units (human & AI) should warp less online
    * Ability to replace CD music w/ OGG files
    * More crash fixes
    * Easier to host games w/ automatic UPNP, Windows Firewall support(*)

*: requires router w/ UPNP support, and Windows Firewall as your primary firewall; other firewall software/hardware will still need some manual attention

A number of tweaks and enhancements of the 1.3 series are: are:

    * Much greater MOD (game modification) support, allowing up to 26 total races to be active at once. Many MODders have been among 1.3 beta testers, and have been working to take advantage of the new features. [Their participation or nonparticipation is their own business; no support for 1.3 is implied or MODs promised by us.]
    * Developed/Tested on Windows 2000/XP, DirectX 8.0-9.0b for much better compatability out of the box. Some testers have tested it on Win98/WinME.
    * Many crashes/freezes fixed.
    * Redone audio system that supports far more channels (up to 64) and DirectSound3D for a far more immersive experience. Note: not all sound cards on the market support that many channels; if the driver on your system notes a limit under 64, BZ2 will use that instead.
    * Support for Ogg Vorbis compressed sounds - similar to mp3 files, but with higher quality.
    * Some graphics tweaks: Maximum ingame resolution can be set much higher than 1280x1024 if your hardware supports it. Gamma (brightness) adjustment works on ATI cards.
    * New graphics options like anisotropic filtering, mip bias, more efficient use of graphics card memory with DXT textures improve the visual appeal of the game.
    * Enhancements to many parts of the game, including AI, craft handling, etc.
    * Many more pregame options for IA, DM, Strat & MPI games (feature available to MODs to define custom options pages on a per-map basis)
    * Bots in DM, and some additional DM gameplay modes.
    * Strategy-CTF game mode -- capture a goal, tug it back to your recycler to win, on 6 classic maps. Finally a good use for tugs in MP!
    * Over 50 additional Instant Action & Multiplayer maps by several mappakers within the BZ2 community, and tweaks to some existing maps to reduce bugs. As of 1.3pb4, there are 19 classic & additional IA maps, 101 classic & additional MP maps installed.
    * Several additional security measures to make cheating in multiplayer much more difficult; deliberate remote crashing of games should be fixed.
    * New BZ2 editor screen layout files contributed by testers to expose more functionality that was already there.
    * Ability to rotate buildings (on 90-degree increments) for even more base-building fun
    * Updates to the manual (located in the Extras folder where BZ2 is installed to) to give updated and more accurate information
    * Includes over 800Kb of text files listing changes made since 1.2. This changelog contains our (minimalist) notes as to what changed for each version, and isn't guaranteed to be easily understood. But, it may be useful reading.

For now, this patch will be pretty much English-only. If you have a foreign (French or German) version of BZ2, this patch will replace a lot (but not all) of the files used to display text ingame with English. Voiceovers and other sound effects will remain in the installed language. A translated version of these text items may happen at a later time.