Malicious dupes often feature "Infinite Loops" of constraints. For example, welding Prop A to Prop B, then Prop B to Prop C, and finally Prop C back to Prop A in a way that creates a recursive physics calculation. When unfreezed, the math required to solve the movement breaks the server's tick rate. 3. Entity Overflow
While many are banned from the Steam Workshop as soon as they are identified, these are the typical methods used: Entity Spam: gmod server crasher dupe