Dragon Endurance is a hidden game mode in CastleMiner Z that can only be unlocked when a player finally kills the Undead Dragon in Endurance Mode. After you unlock this game mode, you may go back to the main menu and select whether to play it alone or with friends. After you have selected it, you may choose your map. This gamemode is similar to endurance because the goal is to get as far as possible. Remember that in Dragon Endurance there are no common undead, except for skeletons in caves, and aliens at alien crash sites. The only enemies you'll be fighting on the surface will be dragons. Dragon Endurance is recommended for experienced players only due to the intense dragon combat. At the current release, loading a world that has been played in a different mode will case your inventory to reset, so if you're farming the dragons' drops for a survival world, it is a good idea to first put your items in a crate near the start position or teleport position so you don't lose your items.
In Dragon Endurance, you and your squad are being constantly bombarded by dragons. It can be very difficult to survive for long periods of time, as the strength of the dragon increases as more are killed. The order of the dragons is Fire, Forest, Sand, Frost, Undead. After you kill the Undead Dragon it goes back to a fire dragon, but it is much more powerful that the first Fire Dragon, then it moves on to a more powerful Forest Dragon, then Sand, etc. So once you've killed a good number it can be very difficult to kill them, and probably not even worth the ammo it takes. The difficulty resets whenever you exit the game, so if you're farming the drops (e.g. explosive powder) then after killing a few it can be a good idea to exit to the Main Menu and go back into the game. This gives you the ability to kill dragons faster and conserve ammo.