You may have noticed the strange symbols on your weapon. Here I'll explain what those are. There are four types of weapon damages. 1. Kinetic: This is the "Normal" damage type, no elements applied (White symbol) 2. Solar: This is the fire damage type (Red/Orange) 3. Void: This is the, what my guess is, "Darkness" damage type (Purple Symbol) 4. Arc: This is the electric damage type (Blue) Certain enemies have a shield (Hive Wizards, Fallen Captains). You need to pay attention to the color of the shield to get the damage bonus for these weapons. The Fallen Captain has a blue shield and while the shield is up, he will take no head shot damage. However, you can shoot him with a the appropriate color element i.e. Arc damage to get his shields down quicker. When you use the right damage type, the damage indication number will be the color of the element you used. Source: [spoiler]https://www.youtube.com/watch?v=uTLosBMLt3Q&list=UUkmAjbIecTIjTQctolYeuDw[/spoiler]