Do things like Ork Deffkoptas and Space Marine Bikes have to be within 2" or 4" coherency?
Do things like Ork Deffkoptas and Space Marine Bikes have to be within 2" or 4" coherency?
2".
4" Coherency is for Vehicle Squadrons only.
Units of more then one vehicle operate as squadrons, but ork deffkoptas and space marine bikes are jetbikes and bikes respectively, not vehicles.
Yes, they are vehicles in the sense they are machines that transport individuals, but that's real world thinking. 40K does not classify them as vehicles. The army list section of each codex will tell you "Vehicle (which kind)" in the Unit Type if it is a vehicle.
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