I discovered recently that the SS2 manual doesn't actually say what differences the selected difficulty makes. So I figured it would be useful to attempt to document everything the difficulty affects. This is what I have so far:

As difficulty increases...
- Base max hit points decrease
- HP gain per level of endurance decreases
- Base max psi points decrease
- Replicator prices increase
- Stat/psi upgrade prices increase
- Useful items are removed from the world
- More hazards are added to the world

On Easy difficulty only:
- Resurrecting after death is free (otherwise 10 nanites)
- Healing items are 50% more effective
- Hostile creature population limits are reduced by one, probability of spawning beyond the minimum population limit is halved, and respawn interval is doubled

Anything else? Anything above that I've imagined but isn't actually true?

Aside from items being removed in the world, there are also fewer security computers on most maps. I have a lot of this stuff privately documented for my own purposes, though a lot of it is mixed in with SCP info.

I'm not sure about new hazards being introduced on higher difficulties. Can you give me an example of that?

Just discovered something else. On Easy, psi hypos restore 50% more psi points.