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Note that all controls are fully customizable now.

Control	Usage
	Move the cursor.
	Attack target, move to location, select items, navigate menus.
+Shift	Attack location while standing still, instantly sell or buy items (vendor window). Can be used to fix the invisible character glitch.
	Attack target using assigned/equipped ability.
	Zoom in.
	Zoom out.
1, 2, 3, 4, 5, 6, 7, 8, 9, 0, -, =	Use the item or equip the ability that is sitting in one of the activeslots on the user interface.
F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12	Equip the ability that is assigned to that hotkey (known as hot spells). Alternatively assigns an ability to that hotkey when placing the cursor over an ability icon in the skills menu.
←	Move left.
→	Move right.
↑	Move up.
↓	Move down.
`	Orbit the camera (currently does nothing).
Insert	Reset camera orbit.
Numpad 7 or Q	Orbit the camera left.
Numpad 9 or E	Orbit the camera right.
C	Display your character statistics and details.
I, B	Display Inventory
K	Display skills menu.
L	Display the Quest log.
M	Display the atlas/maps.
V	Toggle third person rotational viewing mode; also known as "Vanity Cam."
X	Toggles between weapon sets.
ESC	Display the main menu.
Num Lock	Toggle Auto-run.
Print Screen	Takes a screenshot. Screenshots are saved on the drive you have Windows installed on, and can be found by going to "Drive:\Documents and Settings\profile_name\profile's_documents\My Games\Mythos\Screenshots" ("profile's_documents" will probably be called "My Documents"). Note that some keyboards label their print screen button differently - "Prnt Scr", "PrtSc", and other variations are all possible. Also, using this key may not work for you as expected - either it won't save a file, or it won't act as normal (copying the image to your clipboard, where you could normally paste it into a graphic editing program like MSPaint). Alternatively you can use the /screenshot command.
Print Screen+Shift	Possibly takes a screenshot and copies it temporarily to your clipboard. This may not work for everyone.
Shift	Hold position.
Space	Used to close all open menus on the screen.
Tab	Toggle the automap (minimap) on or off.

[edit] Breaking Animation - Speed Attack Glitch

By spamming (tapping or holding) certain buttons while using abilities with , you can cause the game to break your character's animation and reset the skill to reduce the attack or casting speed to a fraction of what it is normally. Many buttons work, such as F and G, and Space. You can use this to your advantage until the bug is fixed.