Sneak

Skill Sneak
Modifies	Chance of being detected while sneaking
Initial level	5% + 3 x Agility
Related perks	Silent Running, Ghost, Silent Death, Thief
Related traits	Small Frame

"Quiet movement, and the ability to remain unnoticed. If successful, you will be much harder to locate. You cannot run and sneak at the same time, unless you take Silent Running perk."

Sneak allows a player to become totally invisible, unless he performs an attack. If he has the Silent Running perk, he can even run while being sneaked, which allows him to infiltrate enemy lines, for example. However, players can see you if you get too close to him, depending on many things (See the Modifiers section for more informations).

Modifiers

Sneak is subject to many modifiers, its mechanics differ from those of Fallout1/2. These modifiers are constantly checked by the game.

• FOV: When your character is out of the opponents Field Of View, the sneak is automatically successful.
• Minimum distance: Up to 3 hexes from opponent, your character is always visible, regardless your sneak skill.

Bonuses

• Ghost perk: +30% (can't increase skill above 300% cap).
• Occluders: Standing behind scenery objects like barrels, tables (up to 2 hexes from them) gives you +50% bonus.
• Having active Stealth Boy in one of active slots gives +60% to the Sneak skill.

Penalties

• Weight: -1% per 1 kg of the total weight of items you carry.
• Armor:
  • Leather Armor and Leather Armor Mark II: -25%
  • All metal armors and combat armors: -50%
  • Powered armors (PA, APA, etc.): Sneak is disabled.

Against an opponent

• Direction - direction of the opponent has big impact, basically, the area around opponent is divided into four parts, and each part modifies your sneak skill value as follows:
  • Front: -135%.
  • Front-sides: -95%.
  • Back-sides: -55%.
  • Back: -15%.
• If your opponent has active motion sensor in an active slot, he will have +2 Perception for the purpose of sneak detection (not capped at 10).

Actions that make you visible again

The following actions may remove your sneak, and make you visible again to your enemies' eyes.

• Attacking.
• Running (If you haven't taken the Silent Running perk).
• Wearing a powered armor, as said above (PA, APA, etc).
• Looting containers and bodies by "take all".
• Looting bodies while sneaked has 50% chance of desneaking.
• Picking up items from the ground while sneaked demands successful steal test. The weight is checked.

Formula

After all bonuses and penalties have been applied, the final formula, which determines the maximum distance between the observer and the (sneaked) observed at which the latter is visible is:

20 + opponent's Perception * 3 - previously calculated skill / 6