An Environment Effect is a special type of effect caused by terrain that you are passing through. For example, Tar, found in Ascalon, which lowers your speed by 33% or Icy Ground, as found in Marhan's Grotto, which causes you to move 70% slower.

In the Effects Monitor, Environment Effects have a green border like enchantments, but unlike those they cannot be removed or prevented in any way except to leave the location.

Note: In the Prophecies campaign, Environment Effects are not officially labeled as such in the skill description, but they are labeled "Spell" or "Signet", which is misleading, as these labels may be misinterpreted that the effect is being cast by someone, and that countermeasures that work against other spells or signets might work against Environment Effects, too. That is, of course, not the case.

For a list of Environment Effects (officially labeled ones as well as unofficial ones), see Category:Environment Effects.