Firewalker Pack is a downloadable content (DLC) pack for Mass Effect 2. It adds the heavy hover tank "Hammerhead" which is basically the successor of the Mako from Mass Effect and has an automatic target acquisition. The quest series consists of five missions where the player through linear levels respectively collects data packages.
The DLC is available for free after registering for the Cerberus Network, the Bioware online platform. Every new copy of Mass Effect 2 includes a code which can be used once.