Rule: Area conditions

Fighting on a slippery surface or in the midst of a whirling storm is restrictive. Areas subject to such adverse effects have an Area Condition. Conditions can change during the course of combat.
For example, setting fire to an Area would add the Harmful Condition… and putting it out would remove it.

Harmful

Areas plagued by extreme cold, fire, or other damaging effects, are Harmful. When in a Harmful Area…

If you are not adequately protected from the source of the harm, you lose 1 Heart when entering the area, and another for each subsequent Turn you remain in the Harmful Area (at the end of your Turn).
If you are reduced to 0 Hearts because of the Harmful Area, you must roll an Injury from a table determined by the GM (a table that reflec the kind of harm of the area).

Obscured

Areas that are partially or totally dark are Obscured. When in an Obscured Area…

Partially dark: You suffer a Disadvantage on rolls that require precision, perception or aiming, including Attack rolls!
Totally dark: You suffer the Partially dark effect, and also a Major Penalty (-4).

Sheltered

Areas with features that offer protective cover from Missile Weapons are Sheltered. When in a Sheltered Area…

Any Attacks directed at you from outside the Sheltered Area suffer a Disadvantage.

Cramped

Areas that are small and restrict movement, such as an alcove or a prison cell, are Cramped. When in a Cramped Area…

The Defense Rating of your Speed does not apply.
Weapon Types other than Unarmed, Concealed, and Small Mechanical incur a Minor Penalty (-2) on Attack rolls.

Your GM will consider your relative Species size when applying the Cramped Condition.
For example, a Small person would still have room to manoeuvre in a tight space, whereas a Massive foe may find a human-sized space restrictive.

Isolated

Areas that are blockaded, elevated, or difficult to enter from other Areas are Isolated. When moving to (or from) an Isolated Area…

When you attempt to enter or leave an Isolated Area, you must use an extra 15 feets. If you have a Slow Speed, this means you would need 2 Turns to enter an Isolated Area!
Isolated rules might only apply in one direction, depending of the obstruction.
For example, a barricade might be designed to be difficult to enter but easy to leave.
If attempting to enter an Isolated Area that requires you to climb, you must make a Strength or Dexterity Check.

Precarious

Areas that are difficult to balance on, like a surface covered in ice or slippery liquid, are Precarious. When moving to a Precarious Area…

You must make a Dexterity Check or be Prone with your Turn ended abruptly.
If the Precarious Area is elevated, such as a slippery roof, and you fail your Check, you will slip and incur a Falling Injury.
You can avoid the Dexterity Check if you forfeit your Action.