Trait Scaling

The traits Alien DNA, Terra Firma, Spaced, and Serpent's Embrace use flat, non-scaling Health and Oxygen values. Health grows dramatically with level, making that part almost useless. Meanwhile, Oxygen never grows, so that part of these traits is actually too powerful. To fix their balance, these traits need to have effects that actually scale.

Terra Firma and Spaced now have you take 10% less damage and use 10% less oxygen in their respective environments, while you take 10% more damage and use 10% more oxygen in the opposite environment. Importantly: these both intentionally also affect damage taken in ship combat. Non-ship space combat is rare to the point that Terra Firma was almost pure benefit and Spaced was never worth taking. With this change, you now have a worthwhile tradeoff for both traits, because your acclimation now extends to your ship handling. The 10% value is useful when positive without being overly punitive when negative.

Serpent's Embrace gives 5% less damage taken and 5% less oxygen used if you've jumped recently (within 4 hours real-time, a value I haven't touched), and you take 5% more damage and use 5% more oxygen otherwise. The 5% less/more damage taken effect also applies to ship combat, for consistency with Terra Firma and Spaced, and because it thematically makes sense.

Alien DNA I changed more. Giving resistance to damage in exchange for less healing means no net change to effective health (or different values would mean it's strictly positive or strictly detrimental), so it needed a different effect. Alien DNA now makes medicines and chems last 20% less duration (which is 20% less healing from medicines), but food and drinks are 20% more effective. This makes the effect a little more beastly in that you rely on eating rather than science. If you're worried that food isn't very good, try my mod Good Food.

Still prefer medicine to food? The new Synthetic Heart trait is the exact opposite of Alien DNA, making chems and medicine last 20% longer and food 20% less effective. Alien DNA and Synthetic Heart are exclusives, so you can only have one.

Using this on an existing character is fine. The existing effects are set to just shut off. Also available on Nexus: https://www.nexusmods.com/starfield/mods/11599/