To activate: While playing TA press enter and the type:

Multiplayer Skirmish Cheat Codes: [These codes let you 'tweak' multiplayer and skirmish games]
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+ATM Gives you 1000 metal and energy.
+Bigbrother Units will say different things when you move them.
+bps Show the data transfer in multi game.
+CDSTART Starts CD Music.

+CLOCK Adds an in-game clock.
+COMBUSTION Kill all other players' units.
+CONTOUR# Displays a 3D contour, # = 1-15.
+CONTROL# Lets you to control a different skirmish AI.
+DITHER Dithering instead of line of sight.
+DOUBLESHOT All weapons do twice the damage.
+HALFSHOT All weapons do half the damage.
+honk Makes units honk when they stop.
+ILOSE Causes you to lose.

+INFRARED Toggle fog of war
+IWIN Causes you to win.
+KILL# Kills off a player, where # is 0-4.
+light Hide the shaded object & Makes all buildings dark.
+logo Change your color ( not tested in multi ).
+LUSHEE Limited resource increase.
+makeposter Huge screen shot of the whole map in BMP format.
+mapping Covers screen with darkness.
+METEOR Causes a random meteor shower.
+Nanolathing Nanolathing x2 but also 2x metal using.
+NOENERGY Drops your energy to 0.
+NOMETAL Drops your metal to 0.
+NOSHAKE Stops explosion screen shakes.
+NOWISEE Full map and disables line of sight.
+RADAR 100% radar coverage. +ReloadAIProfiles Reloads AI.
+screenchat Enable/disable chat text in multi.
+SETI Toggle radar minimap on/off.
+sfx Enable/disable SFX.
+sharemapping Share radar information.
+shareradar Share radar information.
+shootall Units target everything of the enemies.
+showranges Hold shift while mouse is on unit and will show range.
+SING This command makes units "sing" when given orders.
+SWITCHALT Allows you to switch between squads with # keys instead of with ALT+#.
+TILT Max out men and material.
+VIEW# Lets you see how much metal and energy a player has.
+ZIPPER Speed up unit-building process.
Campain Cheat Code: [This code will let you play any level in any order]

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Click on Total Annihilation's Single Player icon. When the Single Player Game page appears type DRDEATH (it is not case sensitive). This will cause a Cavedog Entertainment bone to appear between the Load Game and Previous Menu icons on the right side of the screen. Clicking on the bone will take players to a special Play Any Game screen where they can play any Total Annihilation mission, even if they have not earned their way to that level yet. Skirmish Cheat Code: [This cheat will let you use up to ten players in a skirmish game]
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When in the skirmish room, type asterisk (shift+8), after that type the roman numeral number of the amount of players you want. For example, if you want 10 players in skirmish mode, you'd type "x", and for five players you'd type "v".
1 = i ; 2 = ii ; 3 = iii ; 4 = iv ; 5 = v
6 = vi ; 7 = vii ; 8 = viii ; 9 = ix ; 10 = x