When hundreds of players fill one screen, as in a siege or a world boss fight, the cost of drawing them is more than the device can handle.
Why Hundreds of players and effects overlap on one screen → Effect Animation, shadow, name tag, and effect costs grow with the player count → On screen FPS drops 60 → 15: all movement stutters, and input lag sets in
Simplify by distance (LOD), cap the number of players shown, offer a simplified effects option, lower the animation update rate.
Ballpark numbers
Even at 0.02–0.1 ms per character, 300 characters add up to 6–30 ms. The frame budget at 60 FPS is 16.7 ms, so this alone uses over 1/3 of it, and at the high end exceeds it.
On the graph
Rises with load · Frame time, characters on screen
Where to look
Compare PresentMon frame time and CPUBusy/GPUBusy before and after a siege or world boss. In a development build, Unreal’s stat Unit (game thread, rendering thread, and GPU time)
Confirmed if
Frame time climbs as more players come on screen and improves right away when a cap on displayed players or the simplified effects option is turned on
Ruled out if
Spikes regardless of player count: “Frame time spike” or “Client garbage collection.” FPS fine but only other players’ movement lags behind: “Packet processing bottleneck on the main thread”
Check with
The player’s own environment
Sources
Introduction to level of detailUnity Without LOD, even objects that look tiny on screen are drawn at full complexity; LOD cuts the rendering cost