The data is shown in the Debug Mode.
The Debug Mode is a feature implemented into the M.U.G.E.N engine that enables the player to see the damage, speed and other stats on-screen. As its name suggests, its main purpose is to detect any bugs a character may possess, but it is mostly used by players as a method of cheating.
The debug mode is disabled by default, but it can be enabled by Ctrl+D. In order for debug mode to be active by default, it must be enabled in mugen.cfg first. It is also possible for debug keys to be enabled while debug mode is disabled, again through mugen.cfg.
Debug keys
The debug keys are enabled by default, but can be disabled by editing the mugen.cfg file that resides in the data folder.
F1
This debug key will instantly K.O. player 2 by setting their Life to 0. Certain characters contain coding that keeps them from being K.O.'d in this manner.
Ctrl+F1
Has the same effect as F1, but K.O.s player 1 instead of player 2.
F2
Sets both players' Life to 1; as with F1, this debug key is also neutralised by particular characters. In M.U.G.E.N 1.1, F2 only reduces player 2's Life to 1, making it similar to F1 and subsequently removing the functionality of Shift+F2.
Ctrl+F2
Sets only player 1's Life to 1.
Shift+F2
Sets player 2's Life to 1. Removed in M.U.G.E.N 1.1.
F3
Maxes out both players' Power.
Ctrl+Shift+F3
Toggles auto-refill of Power bars. Only works in M.U.G.E.N 1.1.
F4
Restarts the current round.
Shift+F4
Restarts the entire match, resetting all variables to their default values, as well as reloading player data.
F5
Sets the time to 0, resulting in a Time Over.
F12
Takes a screenshot of the game, saved in .pcx format (.png format in M.U.G.E.N 1.0 and newer); screenshots are saved in the same location as mugen.exe. This can be used even if the debug keys are disabled.
Ctrl+~ or Ctrl+`
Shows/hides the M.U.G.E.N Console; this can be used even if the debug keys are disabled. Only works in M.U.G.E.N 1.1.
Ctrl+<player #>
Toggles A.I. of specified player. Replace <player #> with 1-4.
Example: Ctrl+1 would toggle the A.I. of player 1.
Ctrl+Alt+<player #>
Toggles existence of specified player. Replace <player #> with 1-4.
Example: Ctrl+Alt+1 would toggle the existence of player 1.
Ctrl+C
Toggles display of collision boxes.
Ctrl+D
Activates debug mode, should it be currently deactivated. Initial activation will show player 1's debug information; further presses of CTRL+D will cycle between each character's (or helper's, if they exist) debug information, until all information has been cycled though and debug mode is deactivated.
Ctrl+F
Cycles through frameskip speeds of Auto (A), 0, 1 and 2. Default is Auto.
Ctrl+I
Forces both players into their standing states (state 0).
Ctrl+L
Toggles display of the Life and Power bars.
Ctrl+S
Toggles speed-up, which makes M.U.G.E.N run at its fastest setting. Will appear to run slowly if the machine being used is not powerful enough.
Ctrl+T
Toggles auto-refill of both players' Life and Power. Only works during Quick Versus.
Ctrl+V
Toggles V-sync, which helps prevent moving images from "shearing".
Space bar
Maxes out time, and both players' Life and Power.
M.U.G.E.N Console
Introduced in M.U.G.E.N 1.1, the M.U.G.E.N Console (also known as mconsole) is a tool used primarily for debugging and testing purposes, activated by pressing Ctrl+~ or Ctrl+` depending on the keyboard layout. Similar to the Command Prompt, the Console has its own set of valid commands, and although most perform identical functions to the debug keys listed above, they can be used regardless of whether or not debug keys are enabled.
It should be noted that player input keys are disabled while the M.U.G.E.N Console is active, so keys that are normally mapped to buttons will have no affect on background gameplay such as menu navigation and character actions. Also, M.U.G.E.N will not close while the Console is active, unless the quit command is used.
clear
Clears the console of all messages and previously typed commands.
changestate <player #> <state #>
Functions like the state controller of the same name, forcing the specified player into the specified state. Replace <player #> with 1-4, and <state #> with desired stateno. If stateno doesn't exit, the specified player will simply remain in their current state, though if an invalid player number is specified, the Console will simply state, "Invalid player specified".
Example: changestate 1 180 would force player 1 into their win state, albeit not actually causing them to win the match.
clearclipboard
Clears the debug clipboard of all messages.
consoletoggle
Hides the M.U.G.E.N Console. Identical to Ctrl+~ or Ctrl+`, though it cannot show the Console, as it needs to be visible for commands to be typed in.
forcestand
Forces both players into their standing states (state 0). Identical to Ctrl+I.
fps
Toggles display of the FPS counter in the top right-hand corner.
framestep
Advances frame by 1. Only works while M.U.G.E.N is paused.
help
Displays a list of all valid commands in the Console, as well as descriptions next to each command.
lifereset
Maxes out time, and both players' Life and Power. Identical to Space bar.
matchreset
Restarts the entire match, resetting all variables to their default values, as well as reloading player data. Identical to Shift+F4.
maxpower
Maxes out both players' Power. Identical to F3.
maxpowermode
Toggles auto-refill of Power bars. Identical to Ctrl+Shift+F3.
pause
Pauses M.U.G.E.N. Identical to pausing the game using the Pause key, but it also functions on menus and vs. screens, albeit with some graphical issues.
quit
Closes M.U.G.E.N.
roundreset
Restarts the current round. Identical to F4.
screenshot
Takes a screenshot of the game in .png format. Screenshots are saved in the same location as mugen.exe. Identical to F12.
setlife <player #> <life #>
Sets the current Life state of the specified player to a specified amount. Values lower than or equal to 0 will K.O. the specified player, while values higher than the maximum Life for the specified player will simply max out the specified player's Life. Replace <player #> with 1-4, and <life #> with desired Life value.
Example: setlife 1 0 would set player 1's Life state to 0, subsequently K.O.ing them.
Please note that characters that are immune to F1 and F2 cannot have their current Life stats altered through this command.
setroundtime <timeleft #>
Although the official documents for M.U.G.E.N 1.1 state that this command sets the timer of the current round to a specific value, the specified value currently represents how many ticks the timer is away from a Time Over, as opposed to a specific value on the timer. If the timer is set to infinite (-1) in mugen.cfg, then this command will have no effect; likewise, if the timer is not set to infinite, this command cannot set it to infinite.
Example: setroundtime 60 would set the timer to 60 ticks (1 second) until a Time Over.
showclsn
Toggles display of collision boxes. Identical to Ctrl+C.
toggleai <player #>
Toggles A.I. of specified player. Replace <player #> with 1-4. Identical to Ctrl+<player #>.
Example: toggleai 1 would toggle the A.I. of player 1.
togglelifebars
Toggles display of the Life and Power bars. Identical to Ctrl+L.
toggleplayer <player #>
Toggles existence of specified player. Replace <player #> with 1-4. Identical to Ctrl+Alt+<player #>.
Example: toggleplayer 1 would toggle the existence of player 1.