Tekken 6 features bigger stages with more interactivity than its predecessors such as walls or floors that can be broken to reveal new fighting areas. The character customization feature has been enhanced, and certain items have implications in some aspects of gameplay.
A new "rage" system has been added, giving characters more damage per hit when their vitality is below a certain point. Once activated, a reddish energy aura appears around the character, and their health bar starts to flicker in red. The rage aura can be customized with different colors and effects to appear like fire, electricity, ice, among others. Another gameplay feature added is the "bound" system. Every character has several moves that, when used on an opponent that is currently midair in a juggle combo, will cause the opponent to be smashed hard into the ground, bouncing them off the floor in a stunned state and leaving them vulnerable to another combo or additional attack. As of the Bloodline Rebellion update, successfully parrying a low attack will also put a character into a bound state.
The console versions (excluding the PSP version) also include an extra mode entitled "Scenario Campaign" which bears similarities with the "Tekken Force" and "Devil Within" modes from previous installments. In this mode, the player can move freely in an environment similar to that of a third-person role-playing game. Players can also pick up weapons such as poles and gatling guns, along with lootable items, money, and power-ups which can be found inside crates that are scattered all throughout the playing environment. Players can move freely between fights, but when a group of enemies are encountered, the gameplay switches to the traditional, two-dimensional Tekken style. This mode originally only had single player offline. Namco released a patch on January 18, 2010 that allows online Co-op mode for Scenario Campaign.
Both the PlayStation 3 and Xbox 360 versions of the game include an online versus multiplayer mode over PlayStation Network and Xbox Live respectively.It includes Ranked Matches mode, where the player can promote their character to a higher ranking, and Player Matches mode, where the player's fights aren't ranked and they can invite friends to have matches with them.