A bloodsucker. This symbiotic burst-rifle leeches health to forge its ammo and then restores health with each headshot.
The Hema is a burst-fire Infested rifle that requires a sacrifice of health in order to reload, but in turn fires accurate three round bursts of Viral agents that can slash the health of an enemy by half. The weapon also inflicts lifesteal upon headshots, transferring damage dealt to enemies to the player.
The Hema is a highly accurate rifle that heals the player on headshots. To reload however, the player must lay out their arm as the weapon sucks some of their health. It will drain between 1% and 3% of the player's max health depending on how much ammo needs to be replenished to the magazine.
Like all burst fire weapons in Warframe, you must time your clicks in order to fire the weapon at its maximum speed. Mashing the fire button will only stall and fire the weapon at different rates. Frame rates below ~30 FPS will also begin to slow the weapon down.