citizen_lion

From reading the comment here that some stages are more challenging in "difficult" versus "expert", I tried playing in difficult a bit to find out what the differences are. Since the AI in BI2 does not cheat, sometimes more realistic simulations of battlefield rules like in Expert hurts the AI more than it hurts you.

The differences (that I've found so far ):
- Terrain concealment rules: Mountains block radar very well in Expert. Infantry units on a mountain is almost as detection proof as behind an Elixir. I think there is a degree of this in other terrain types too, but much less so.

- Unit occlusion rules: a unit blocks the unit behind it in Expert more than in Difficult. Having a Troll on a mountain will often block the unit behind the mountain as well, even to a radar tank.

- Crowd impediment rules: in Difficult, if you have a clear path of movement, but there is an enemy unit standing right beside this path, you can still move through. In Expert, you cannot. This works both in and against your favour. So if there is a troll unit right in front of a base you want to capture, and you see it (both the troll and the base), you still need an extra turn to capture the base because you must first move beside the troll. Sometimes this rule appears to be broken, but I think that it's actually because the scout bike has so much movement that it sometimes goes around the impediment instead.

- Vision advantage: if you "see" an enemy unit and the area surrounding it more clearly that it "sees" you, you will get an advantage in an otherwise equal skirmish. I'm not exactly sure about the mechanics of this, but I can reliably get a slightly favourable outcome by maximizing all the occlusion and jamming that I can get, while painting enemy units with radars.

- Ballistics: in Expert, the effect of ballistics changes geometrically to experience instead of linearly. This is closer to reality, as accuracy is really important in any kind of shooting regardless of the power of the warhead (anything less than nuclear). In Expert, a level 1 quasar and skull, or even pulsar or archimedes, has nearly no chance of inflicting ANY damage on any unit other than infantry. I have often failed to inflict one damage on a half-strength technotrax with a full-health pulsar level 1 unit. So basically, you cannot rely on artillery early in a battle, or in any fast push (because having to move them means that they will not level up as fast).

- Landing costs fuel: a subtle and insidious rule, but very true to life. It takes quite a bit of fuel to land an aircraft. If an aircraft is right next to its base, and there are 3 bars or fewer of red left, it will not go in even with the most favourable weather, and will die.