More fixes to game balance, and no more Curse of Undeath

The Curse of Undeath is gone now; as long as capital cities are immortal, it's unfair to saddle them with an unbreakable curse, so unless that rule ever gets changed, the Curse of Undeath is not coming back. The Undead are weaker in general, with a smaller bonus against cities and a debuffing against anything besides cities - after all, everyone knows that individual zombies are weak, and it's only in numbers that they're fearsome. The debuffs on science and culture have been redone, so they no longer require percentages or specific buildings.

Also gone is the Fast Fossil Fuel, because that one is moving to its own mod. I'll be making a mod that adds that building and at least one other, all of which give you the ability to change outdated resources into more currently useful ones.

README.md

@@ -1,3 +1,7 @@
 A zombie plague has broken out in the world of Unciv... and if you like, you can be the zombies! Devour and conquer the world with your tireless flesh-eating army!
 
-There's a catch, though: the undead cannot build. They can only infect (and they're not so great at trading). Your only way to acquire new cities is to conquer them. Fortunately, you're pretty good at that.
+There's a catch, though: the undead cannot build. They can only infect (and they're not so great at trading). Your only way to acquire new cities is to conquer them. Fortunately, you're pretty good at that.
+
+About this mod: The Undead are designed to be very, very different from your average UnCiv civilization. They cannot build Settlers to settle new cities, they cannot generate Great Merchants to conduct trade missions, they're bad at culture and they're very bad at science. So what are they good at? Devouring. They build units quickly, they can sustain a large army cheaply, and they're never, ever unhappy. They roll forward without ever stopping to rest, devouring everything in their path. They are especially good at fighting cities and conquering city-states, and their short-range units heal when they kill. If you're in the mood for total war, the Undead are for you.
+
+Be warned, though: individual zombies are weak! It's only in numbers that they are strong.

credits.md

@@ -1,6 +1,6 @@
 Icons adapted from the Noun Project:
 
-Nation icon/Undead promotion/Curse of Undeath: [Skull by Vladimir Belochkin](https://thenounproject.com/term/Skull/1030702/)
+Nation icon/Undead promotion: [Skull by Vladimir Belochkin](https://thenounproject.com/term/Skull/1030702/)
 
 Arms Merchant: [dollar target by Rockicon](https://thenounproject.com/term/dollar-target/472861/)
 
@@ -20,10 +20,6 @@ Lich King's Tomb: [Ankara by ProSymbols](https://thenounproject.com/term/ankara/
 
 Graveyard: [graveyard by Nikita Kozin](https://thenounproject.com/term/graveyard/573169)
 
-Fast Fossil Fuel: [petroleum by Andrejs Kirma](https://thenounproject.com/term/petroleum/2649102/)
-
-Unused Courthouse: [Judge by Krisztian from mokapot.hu](https://thenounproject.com/term/Judge/1076388/)
-
 Memento Mori: [Tombstone by Sneha](https://thenounproject.com/term/tombstone/2915140/)
 
 Abyss: [canyon by iconfield](https://thenounproject.com/term/canyon/3005193/)
@@ -34,12 +30,10 @@ Necromancer: [necromancy by HeadsOfBirds](https://thenounproject.com/term/necrom
 
 House on a Haunted Hill: [Haunted House by sumhi_icon](https://thenounproject.com/term/haunted-house/1387450/)
 
-Mass Grave/Strength of the Grave: [Mass Grave by Dan Hetteix](https://thenounproject.com/term/mass-grave/75126/)
+Mass Grave: [Mass Grave by Dan Hetteix](https://thenounproject.com/term/mass-grave/75126/)
 
 Demi-Lich: [Skull by Karsten Barnett](https://thenounproject.com/term/skull/47649/)
 
-Skeleton Dance: [Skeleton by Lele Saa](https://thenounproject.com/term/skeleton/689675/)
-
 Tasty Brains: [Brain by AFY Studio](https://thenounproject.com/term/brain/1455525/)
 
 Hearse: [Carriage by Elijah Meeks](https://thenounproject.com/term/carriage/3036/)

game.atlas

@@ -4,86 +4,58 @@ size: 2048,256
 format: RGBA8888
 filter: MipMapLinearLinear,MipMapLinearLinear
 repeat: none
-BuildingIcons/Curse of Undeath
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 BuildingIcons/Germ Warfare
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 BuildingIcons/House on a Haunted Hill
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 BuildingIcons/Infection
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 BuildingIcons/Lich King's Tomb
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 BuildingIcons/Mass Grave
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 BuildingIcons/Memento Mori
   rotate: false
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 BuildingIcons/National Tombstone
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-  size: 100, 100
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@@ -97,14 +69,14 @@ ImprovementIcons/Abyss
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 ImprovementIcons/Graveyard
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 NationIcons/The Undead
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@@ -125,35 +97,35 @@ TileSets/FantasyHex/Tiles/Graveyard
   index: -1
 TileSets/FantasyHex/Units/Arms Merchant
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 TileSets/FantasyHex/Units/Black Death
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 TileSets/FantasyHex/Units/Demi-Lich
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 TileSets/FantasyHex/Units/Ghost
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 TileSets/FantasyHex/Units/Hearse
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@@ -167,7 +139,7 @@ TileSets/FantasyHex/Units/Lich King
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 TileSets/FantasyHex/Units/Necromancer
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@@ -195,84 +167,77 @@ UnitIcons/Bone Dragon
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 UnitIcons/Demi-Lich
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 UnitIcons/Ghost
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 UnitIcons/Hearse
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 UnitIcons/Lich King
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 UnitIcons/Necromancer
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 UnitPromotionIcons/Breach the Walls
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 UnitPromotionIcons/Eat the Living
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 UnitPromotionIcons/Hard to Kill Twice
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 UnitPromotionIcons/Summon the Lich King
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 UnitPromotionIcons/Undead
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