While the Campaign challenges in Call of Duty: Black Ops Cold War are simple enough to complete, the other game modes are packed with tougher objectives. Rare calling cards have always been a badge of honor in Call of Duty, and the latest Black Ops title is no exception to that rule. After all, while plenty of calling cards can be obtained through buying bundles and completing simple objectives, others are far less easy to come by. Call of Duty: Black Ops Cold Warhas no shortage of calling cards to collect, and while nearly all of the titles offer cool designs, some are more impressive than others.