Panzer Corps 2: Axis Operations - 1941

I would say that within the Axis Operation series that 1941 is the first campaign to be firing on all cylinders. This campaign does take a short time to get going as you go through some Yugoslavian and Greece scenarios but once you hit Barbarossa it becomes fantastic (and those preludes aren't bad mind you). The scenarios really do give a good sense of how large the invasion is as you will always be fighting a clock while having to deal with large soviet formations that seriously do present a threat. Then as the campaign goes on you began to slow down as the rain and mud combine with soviet resistance to make taking ground harder and harder. You get a real sense of what feels like a break down of your operational capabilities as it just takes longer to complete missions. This rounds off beautifully with some winter scenarios that contains what I would consider one of the first truly hard bonus scenarios that you will want to complete if the alt history of later Axis Operations is something you are interested in. This is overall a great campaign among one of my favorites in the AO series. The only knock I have when replaying is the slower start with stuff before Barbarossa which can feel like a bit of slog once you've seen what is held later in the campaign. If you are looking for an entry point for when AO got fantastic this is where you want to start.