All engines emit some sort of gas: Steam: ["low temperature"+50] steam (probably boiling/condensation point, so 150C and thus 323K) Petrol: 1500K CO2 Hydrogen: 2000K steam All engines additionally heat up a column 3 tiles wide and 10 tiles tall below them by their exhaust temperature divided by distance from the engine. This is hard-capped at 3200K. For example, 3 tiles directly below the center of hydrogen engine should get +2000K, 3 tiles below them should get +10