Difficulty settings are a option in Commandos added in Commandos: Beyond the Call of Duty and allow the player to tailor the gameplay for how difficult they want it to be.
Beyond the Call of Duty[]
In BTCOD the player is given the option of Easy or Hard when starting a new game.
Playing on the Hard difficulty setting adds additional soldiers to missions and increases the amount of machine gun equipped guards.
Commandos 2: Men of Courage[]
In Men of Courage, the player has the options of Normal, Hard and Very Hard.
On Normal mode, Commandos are only unconscious after losing their health and can be revived via a First Aid Kit while on other difficulties the commando will die and fail the mission.
Commandos take more damage as the difficulty level increases and First Aid Kits and Food heal less.
The fire rate of weaponry used by Commandos will also slow down as the difficulty level increases.
Commandos 3: Destination Berlin.[]
The original release of Destination Berlin removed the option for difficulty settings while the remaster added a new mode called Rookie mode.
Compared to the Original difficulty option, Rookie makes a notable amount of changes:
Commandos take less damage from attacks.
First Aid Kits fully replenish the player's health, notably this appears to unintentionally fix a bug where the player will lose all their first aid from being "auto-used".
All ranged weapons aside from the pistols, submachine gun and MG42 now have increased range for all Commandos.
Strike Force[]
Strike Force has the highest amount of difficulty options in the series with Easy, Normal, Hard and the final unlockable (by getting max stars in every mission) Commando difficulty available to the player.
What exactly changes is on a per-level basis but the general changes the player can expect are:
Commandos have notably higher or lower health and stamina bars depending on difficulty.
More enemies can be added to a level and they gain additional health. (Commando difficulty soldiers can survive a Karabiner 98k shot to the chest as opposed to dying instantly like all previous difficulties.)
Rarely, additional scripted sequences will occur or a level being more difficult means sequences that occur after a certain amount of time are more likely to trigger as the player is slowed down.
Weapon/Item pickups will be reduced, notably Hard and Commando remove the Portable MG42 entirely.
The starting inventory of the Spy is often changed on Hard and Commando to remove his starting PPK.