8 hours, upgrade progress on gun.
Tracking progress toward the next gun upgrade on the gun itself. As pick ups are collected, there is the emissive notify rolling over the gun and now the gun material itself begins to light up as the count increases. Gun 1 starts grey turns silver, gun 2 turns gold, gun 3 turns gold in a different pattern to track the number of homing projectiles being stored within. The gun are now slightly lit by a light on the first person character. Emissions on pick up acquired change color with the gun's level. Level 3 gun does not emit light on pick up acquired. Light emission fade period divorced from frame rate. Gun glow to denote progress and ammo tracking creeps up the gun over the course of seconds. Creeps down too as homing projectiles are fired.