As I have played alot of SpringRTS engine games like Zero-K which has the most advanced projectile physics gameplay in a largescale RTS I have seen. Men of War propably have more advanced projectile physics but it is more like an RTT than an RTS. Projectiles typically pass through your own units in TA and SupCom. Do note however that projectiles didn't pass through allied units in SupCom which made it harder to combine forces as you risk hitting your allied units if they came infront of you. You could give the ally your units to avoid this to some degree atleast. If projectiles can go through your own units I think they should pass through friendly units aswell in a teamgame with fixed teams. I'm not sure how it should work in a Free For All game with dynamic alliances where you can ally and brake alliances. SpringRTS games can choose if projectiles pass through friendly units or not. Weapons Line of Fire check terrain and can be set to avoid friendly units and features(wrecks, trees and such). Friendly unit blocking makes micromanagement much more complex as enemy units can take cover behind friendly units for example. When there is a friendly unit between the attacker and the target in range the decision where the attacker should move to gain Line of Fire is not trivial. Should the attacker move to the left or right? Should the attacker path straight against the enemy and stop to fire as it passes the friendly unit? Should the unit move to the closest spot where it got free line of fire? In Spring games custom formations(formation line draw) mitigate this somewhat as the players can keep units on a line to attain maximum firepower without units blocking each others Line of Fire. Gameplay design that can decrease the need of micro in a game where friendly units block Line of Fire: Arcing trajectories. Long range in relation to unit size. Line draw formations. Unit automatization or AI. What I suggest: Projectiles should pass through own and allied units. In an FFA with dynamic alliances projectiles should also pass through allied units. What I would prefer: Friendly units block Line of Fire. Long ranges. Group AI that keep units on a line and maximise firepower.