Crimsonland is a simple top-down shooter in which, depending on the mode, the player attempts to survive as long as possible or through multiple waves of enemies
Crimsonland starts the player in the middle of the screen, and creatures begin swarming the player soon after the level starts. The player must avoid being completely overrun and killed by running around the screen and shooting the enemies, which may drop power-ups and weapons that increase the player's power.
The player aims with the mouse, pointing a reticle in the direction he wants to shoot. Movement is handled with WASD or arrow keys. The control scheme is similar to some PC adaptations of dual-joystick shooters. If the level chosen is a campaign level, the player must survive until the waves of enemies stop. If it is challenge mode, then the player must survive as long as possible. The further a player has reached in the campaign, the more powerful weapons will be available in challenge mode.
There is an extra mode that forgoes the normal gameplay to instead use typing to kill enemies in a manner reminiscent of The Typing of the Dead. The player is stuck in the middle of the screen, unable to move. The incoming creatures have a label with a single word chosen from a random assortment words that must be typed in to kill that assailant. As the player progresses, longer and harder words are given and enemies attack faster and faster. If an enemy reaches the player and they are not shot off before they deplete the player's HP, the player loses.
Quest mode consists of 50 levels, split into five chapters, each level getting progressively harder. The player begins each level with only a pistol, but as more and more levels are completed more weapons and power-ups become available. There is also "Hardcore" mode that is unlocked after beating all of the levels in normal; this is similar to normal, except more enemies appear.
Players encounter a large amount of enemies, and only have a assault rifle to fend them off with. There are no perks or power-ups in this mode, the goal is to survive as long as possible.
Players are placed in a never-ending level that; as this mode progresses, enemies appear more frequently get progressively harder.
A game mode where players have to type out the monster's word instead of physically attacking them.