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At "Hardcore" and "Nightmare!" difficulty levels, bots have no handicap and significantly faster react time and turning speed. They can only deal a certain percentage of damage and carry limited amount of health and armor, anything above that limit will decay slowly. On "I Can Win", "Bring It On" and "Hurt Me Plenty" difficulties bots are handicapped respectively 50%, 70% and 90%. The easier difficulties will make the bots inaccurate, handicapped, ignoring the power-ups, very slow to react and turn whilst the harder difficulties will make the bots fast as a pro-player, no handicap, gathering power-ups whenever available and more accurate than humanly possible, presenting a true challenge. Depending on each difficulty will depend on the skill of the bots in each map. The difficulty levels are " I Can Win", " Bring It On", " Hurt Me Plenty", " Hardcore" and " Nightmare!". All of them can be selected when starting any Singleplayer map. In Quake 3, there are five difficulty levels instead of the normal four. This makes Gunners, Icarus and Tanks much more difficult. Hard+ makes the enemies' attacks faster and there is a much lower chance of any of the enemies flinching. This will put the player in the very first level with the difficulty of Hard+. Hard+ (which is the same as Nightmare in Quake) is again hidden and can only be selected by typing "Skill 3" and then "Map Base1" in the console. These are chosen from the Singleplayer menu, and choosing one will begin a new game in that difficulty. In Quake II, there are again 4 difficulty levels which are pretty much the same as Quake's but with slightly different names. This makes it possible to complete Shub-Niggurath's Pit on Nightmare without cheating, as long as you were on this difficulty before starting The Elder World. If you don't change the difficulty through either method at any time, then it will remain the same throughout your playthrough.
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If you use the latter method to change the difficulty after completing The Elder World, you cannot play any other episodes or Shub-Niggurath's Pit on Nightmare without cheating again, depending on the order you play the episodes in.
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