Better Mechanics : Terrain & Width

Ever get the feeling that terrain doesn't really mean shit in HOI4? Watched Italy casually sweep through the Sahara? Held a mountain pass with the same effort as a stroll through Belgium? Yeah. Me too.

Better Mechanics: Width & Terrain fixes that in two ways.

Part 1 — Combat Widths

Reworked combat widths inspired by the 1.11 values but with a distinct historical and gameplay flavor. Every terrain type is now meaningfully different from the next. No two share the same standard width.

The philosophy: Plains are wide open. Mountains are a pass fight. Jungle is a nightmare. Urban is both everywhere and nowhere at the same time (Stalingrad said hi). Marsh is just plain unfair and you deserve what you get for going in there.

Terrain

Standard Width

Reinforce Width

Plains

90

45

Desert

86

43

Forest

82

41

Hills

76

38

Jungle

70

35

Marsh

66

33

Urban

96

32

Mountain

60

30

Urban deserves a special mention. 96 base because there is always somewhere to push in a city. 32 reinforce because getting fresh troops into the meat grinder is the actual problem. That ratio is the sharpest in the game and it should be.

Part 2 — Terrain Modifiers

Attack penalties are up. Defence bonuses now exist in rough terrain (vanilla had none, which is criminal). Attrition, supply, and logistics are all pushed harder. Inspired heavily by Darkest Hour and Black ICE, with our own take on everything they disagreed on.

The highlights:

• Mountain: Attack is brutal, attrition is punishing, CAS is half blind. You will lose men just existing there.

• Marsh: The worst supply and truck attrition in the game. Waterlogged ground and disease. Avoid unless you enjoy suffering.

• Jungle: Hardest attack penalty in the game. Sickness, terrible supply, trucks hate you. The Pacific said hello.

• Urban: Best defence bonus in the game. Dig in fast. CAS is nearly useless. Every block is a fortress.

• Desert: Small attack and defence penalty for everyone. No cover, no advantage, just heat and logistics pain.

• Naval terrains: Fjords are minefields. Shallow seas expose submarines. Deep ocean punishes destroyers and light cruisers hard.

Compatibility: This mod will conflict with any mod that modifies common/terrain/00_terrain.txt. That includes Old World Blues, KX and similar total conversion mods that add new terrain types. Might push a compatch integrated in the mod for KX tho, since they add steppe. Other than that you're good to go

Thanks for checking it out! Open to feedback in the comments or the specific discussion down below

Bye!

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