This release adds Natural Gas, reworks how crude oil generates underground, and rebalances the Combustion Generator so liquid fuels are worth the effort of making them. Worldgen has changed a lot, so please start a new world to see it.

Additions

• Natural Gas: a new purple gaseous fuel that rises like the other gases. It burns in the Combustion Generator at 24 FE/t, more than raw Crude Oil but less than any refined fuel.
• Crude oil and natural gas reservoirs: large underground pools that are sealed by bituminous plugs except where they open into a cave. Oil reservoirs fill caves up to a flat level, and gas reservoirs hang from cave ceilings above a flat floor.
• Petroleum caves: small cave systems completely filled with crude oil or natural gas and sealed in a bituminous shell. Breaking the shell of a gas cave lets the gas rise out, and breaking the shell of an oil cave lets the oil flow out.
• Bituminous Gravel, Bituminous Sand, and Bituminous Red Sand: blocks that seal oil and gas deposits. They don't fall. Mined with a shovel, they drop 3 to 7 Bitumen (Fortune applies), or the block itself with Silk Touch.
• Bitumen: a new item. In the Centrifugal Separator, 4 Bitumen and a bucket give a Crude Oil Bucket, 2 Sand Dust, and a 25% chance of Carbon Dust.
• Crusher recipes for the bituminous blocks: each sand gives 5 Bitumen and 3 Sand Dust, and the gravel gives 5 Bitumen with a 25% chance of Gravel.
• Two startup config options for reservoir generation:
  • "Cache Petroleum Reservoir Cells" is on by default and never changes what generates.
  • "Fast Petroleum Reservoir Surface Sampling" is off by default. It's faster, but it may place reservoirs differently for the same seed. Recommended for lower-end PCs and servers.

Changes

• Underground oil lakes are now sealed oil deposits. They're completely full of oil and wrapped in a bituminous shell, instead of being half full of air.
• Surface oil lakes now have a bituminous rim that matches the ground it replaces: Bituminous Sand in sand, Bituminous Red Sand in red sand, and Bituminous Gravel everywhere else.
• Each Combustion Generator burn now lasts 1600 ticks per 250 mB of fuel instead of 400, so every liquid fuel holds 4× as much energy per bucket. FE/t ratings are unchanged.
• Stronger oxidizers are now used up more slowly, based on how dense their Oxygen is. Each burn uses 250 mB of Compressed Air, 125 mB of Oxygen, or 25 mB of Dinitrogen Tetroxide. A generator can now start burning with less than 250 mB of Oxygen or Dinitrogen Tetroxide.
• Liquefying coal and coke now keeps more of their energy: 1 dust and 500 mB of water make 500 mB of Liquefied Coal or Coke (was 250 mB).
• Distilling Crude Oil now gives equal amounts of Light Fuel and Naphtha: 125 mB of each per 250 mB (was 200 mB and 50 mB).
• The Centrifugal Agitator now turns 500 mB of Red Fuming Nitric Acid into 125 mB of Dinitrogen Tetroxide and 375 mB of White Fuming Nitric Acid (was 25 mB and 225 mB from 250 mB).
• JEI now shows fluid amounts for tank inputs and outputs on the Combustion Generator, Blast Furnace, and Sawmill pages.

Fixes

• Fixed oil geyser reservoirs leaving a ring of stone uncut at their widest layer, in the middle of the main body of oil below the geyser.
• Fixed JEI's Combustion Generator page ignoring the oxidizer when it showed energy per bucket. It now matches the oxidizer on display.

Notes for modpacks and datapacks

• Oxidizer fluid data (fluid_data/oxidizers/*.json) now needs an amount field, the mB used per burn. Custom oxidizers without it fail to load.
• The "Fixed Process Time" config is now in ticks per 250 mB burn instead of per bucket. If your pack changed it, divide your value by 4 to keep the old balance.
• Custom fuel_combustion recipes that still ask for 250 mB of oxidizer won't start a burn until the oxidizer tank holds at least 250 mB, even with Oxygen or Dinitrogen Tetroxide. Lower the recipe's oxidizer amount to 25 mB to match the built-in recipes.
• No registry ids were renamed or removed, but worldgen changed a lot. If you adjusted worldgen, test your changes in a new world.