Here is Ultimate Mortal Kombat 3.3 (Formerly Ultimate Boss Mod), which does the following:
-Adds the bosses as Playable Characters
-Uses the New Boss Portraits and New HD vs pics.
-Adds a Ladder mode ending animation for Goro, Kintaro and Shao Kahn
-Changes the "Press Space" message to "Press Start"
-Changes "Noob" to "Noob Saibot"
-Removes "BUG_ME" message when practicing Kintaro and Goro's fatalities.
-Adds The Hidden "Classic" characters to the playable Roster
-Fixes the Infamous "palette swap" glitch for the Classics
-Adds Proper portraits, ladder images and vs jpgs for all Classics
-Removes "BUG_ME" character name when selecting the Classics
-Adds endings for Goro, Kintaro and Shao Kahn (no audio due to game limitations)
-Adds alt costumes for the Classics
-Renames the Classic characters to "Klassics" to be "kool"

-Adds retro costumes for Skarlet and Rain
-Adds alt costumes for all 4 DLC characters
-Adds Retro costumes for the bosses
-Modifies the exe to add the pit bottom and challenge tower to the stages in ladder mode.
-Adds Chameleon and Khameleon to the roster
-Includes wrapper exe that allows Shang to morph into other characters based upon his x-ray meter and Chameleon/Khameleon to mimic stun (aka morph) into retro ninjas.
-Adds Boss Nekropolis to the game, allowing you to view stats and endings of the Bosses and Classics (where applicable)
Ultimate Mortal Kombat 3.3 (Formerly Ultimate Boss Mod)Boss Demo:
Boss Fatality Practice Demo:
Classic Character Demo:
Shao Kahn Retro Costume:
Goro Retro Costume:
Kintaro Retro Costume:
Chameleon Demo:
Khameleon Demo:
*edit*
Updated to list latest features and removed introduction as of 5/15/15