| Event | Intro |
Defence Protocols is the first and only season of the Multivariate Cooperation game mode in Arknights.
Operations[]
Clear OD-1 to access MC operations.
| Test Site #01 | Old Plate Ruins |
|---|---|
| Test Site #02 | Ancient Ruined Tower |
| Test Site #03 | Abandoned Factory |
Engineering Test Indicators[]
| Mission | Reward |
|---|---|
| Destroy 50 Mobile Power Sources across multiple clears of all MC operations. |  160 |
| Clear Old Plate Ruins in Normal Test Mode. | 40 |
| Clear Old Plate Ruins in High-Pressure Test Mode. | 80 |
| Clear Old Plate Ruins in High-Pressure Test Mode 3 times. | 80  2 |
| Clear Old Plate Ruins in High-Pressure Test Mode after using Pulse Defense Modules at least 6 times. | 80  2 |
| Clear Old Plate Ruins in Challenge Test Mode 3 times. | 40  1 |
| Clear Old Plate Ruins in Challenge Test Mode after using Pulse Defense Modules at least 3 times. | 40  1 |
| Clear Ancient Ruined Tower in Normal Test Mode. | 40 |
| Clear Ancient Ruined Tower in High-Pressure Test Mode. | 80  2 |
| Destroy 25 Cheap/Remodeled Second-hand Drones across multiple clears of Ancient Ruined Tower. | 80 |
| Destroy 8 Mudrock Colossi across multiple clears of Ancient Ruined Tower. | 80  2 |
| Clear Ancient Ruined Tower in High-Pressure Test Mode after using at least 8 Snowsant's Safe Escape Cranes/Mr. Booms given by Cheap Second-hand Drones. | 80 |
| Clear Ancient Ruined Tower in Challenge Test Mode. | 60  1 |
| Clear Ancient Ruined Tower in Challenge Test Mode 3 times. | 40  1 |
| Clear Ancient Ruined Tower in Challenge Test Mode after using at least 5 Snowsant's Safe Escape Cranes/Mr. Booms given by Remodeled Second-hand Drones. | 60 |
| Clear Abandoned Factory in Normal Test Mode. | 40 |
| Clear Abandoned Factory in High-Pressure Test Mode. | 80  2 |
| Clear Abandoned Factory in High-Pressure Test Mode after closing Teargas Control Valves at least 5 times. | 80  2 |
| Destroy 25 Retrofitted Gastrucks across multiple clears of Abandoned Factory in Normal or High-Pressure Test Mode. | 80 |
| Clear Abandoned Factory in Challenge Test Mode. | 60  1 |
| Destroy 8 Supercharged Gastrucks across multiple clears of Abandoned Factory in Challenge Test Mode. | 40  1 |