Slitherine

Is there no penalty for fighting in close terrain (jungle, cities...) with non infantry units? There is an efficiency drop when moving in, but not for attacking or defending jungle hexes with tanks for example. PG and PC have a close defense value for this, but I don't see anything like this in OOBP. Or do I miss something?

Nope, this was something that irritated me, too. The game looks very similar but does a lot of things differently.

First, there is indeed no Close Terrain, and therefore no Rugged Defense (risk).

But: Entrenchment is still there and terrain has defense values. Hover over the terrain hex and click INFO to read it.

The Manual lists how COVER works in the game, point 6.7. It's worth reading!

Quote:
For example the M4A3 Sherman 105mm
above is armed with a low-velocity howitzer,
designed for assault and infantry support but not for fighting
enemy tanks. Its “Attack against [Land] Mechanised” (lower-left
corner) has a range of “12-16”.
This means it will have 12 attack against tanks on terrain with
0% cover and 16 attack in 100% cover. If the terrain has 50% cover
it will have 14 attack. This means the unit’s gun is less effective
against tanks on open terrain, where shots would be fired from
long ranges, but its performance improves in towns and cities,
where its high-calibre gun can be used to bettter effect.
The exact calculation for range “X - Y” is:
(X - Y) * (100 - (cover rating)) + Y

This makes Heavy Infantry great in city hexes, they are hard to kill. Bombardment and encirclement/cutting off supply works, very similar to Panzer General/Corps. You still want tanks rather in less difficult terrain, except for close combat specialists like the flamethrower tanks.

Thanks for explaining. I remember reading it, but when I looked at the unit stats in the game I never saw it. I checked for it in game now. It's kind of hidden, because there is only one number for attack listed in the purchase screen, but when you click on the i-icon in your unit list (which I didn't do until now), there are both numbers listed for those units which have a range - i.e. infantry. That's good to know and the "terrain rules" are working.