The ability displays your currently equipped abilities and consumable items (ex. Med Packs, Grenades. These can be added to the tray by either dragging them from your Skill window (default key: K) or backpack to a slot or right clicking. Likewise, they can be removed by dragging them back to the backpack or right clicking with the backpack open. They can also be switched around by dragging them from one slot to another.
When selected, the ability or item's name is displayed, and in the case of stackable items, the amount you have. When using an ability or item with a cooldown period, this delay is displayed in the form of a red highlight. Slots can be selected by pressing 6, 7, 8, 9 and 0, or using E to cycle through them from left to right. Shift+E cycles from right to left.
Several tray rows can be set up and switched between by pressing Shift+1, Shift+2..., up to Shift+5. The use of this is setting up different sets of abilities when 5 slots isn't enough. For instance, an Engineer might have one row for general abilities, one row for his different Turret levels and one for his different Bot Construction levels.
- User interface for the location of the weapon tray on screen.