Attachments
Attachments are another new feature introduced with the Mercenary class. These are Skill Gems that slot into the offhand, similar to Path of exile currency how Quivers are used with Bows. Attachments provide an additional Skill slot, allowing Mercenaries to utilize a broader array of skills compared to other classes.

Attachments can be supported by Support Gems, further enhancing their effectiveness. This system provides an extra layer of customization, enabling players to tailor their skills to specific playstyles or combat scenarios.

Skill Bar Configuration
The Mercenary’s skill bar is designed to accommodate the new mechanics introduced by the Crossbow and Attachments:

Left Click: Rapid Shot
Right Click: Power Shot
Q, E, R: Ammo Skills (such as Armour Piercing, Incendiary, and Permafrost)
T, F: Grenade Skills (Attachments)
For example, the Incendiary Rapid Shot has a larger clip size and increases grenade damage over time. You can throw grenades that explode after a delay, or use Incendiary Power Shot to detonate grenades on buy Path of exile currency the floor instantly.