The Skeleton Key is an unbreakable lockpick that increases your Security skill by 40 points whenever the key is in your possession. You can receive this key by completing Nocturnal's Daedric quest. The Skeleton Key's effect is not a typical skill boost, because the Fortify Security effect is implemented as an ability.
- Even when other lockpicks are in your inventory, locked chests will not use the lockpicks and will instead immediately refer to the Skeleton Key to open the lock.
- In order to break out of a jail cell via lockpicking, it is still necessary to keep an ordinary lockpick in your inventory. The game does not treat the Skeleton Key like a lockpick. If you are arrested, it will be removed from your inventory.
- Having the key in your possession provides access to all "Fortify Skill" options while using spellmaking and enchanting altars.
- Because of the way the key increases your Security skill, it enables you to start the Security Training quest when your base skill is only 30.
- The Skeleton Key makes the lockpicking mini-game impossible to lose: simply use the auto-attempt lockpicking option repeatedly until the lock opens. This is much quicker than picking it manually.
- See skill boost abilities for details on how the key's Fortify Skill ability is different from a standard enchantment.
- If your actual unfortified Security skill is 60 or higher, you cannot directly use the Skeleton Key to level Security: at level 60+, once you add the key to your inventory, the game treats your skill as 100. And you cannot level past 100. If you are only interested in a maxed-out Security skill level, then that's not a problem as long as you still have the Skeleton Key. However, if you are concerned about efficient leveling – for example, increasing your Agility attribute, or your character's Maximum Character Level (if Security is a major skill) — then you will need to take the key out of your inventory to continue to gain any Security experience. Even if Security is a minor skill, having it naturally maxed at 100 is useful just in case you are jailed with one lockpick. But if you don't care about maximum experience or efficient leveling, just leave the Key in your inventory until you stop leveling at 100.
- You can bypass the level 60 limitation mentioned above by dropping the Skeleton Key before you level. However, you still benefit from dropping the Key prior to leveling before level 60, because you can level faster. Prior to level 60 (real level, without the Key), if you drop the Key immediately prior to triggering each level, you will channel the higher level points you get while "learning" with the Key into your low level leveling attempt. If your unbuffed Security level is really low, you can trigger 2-3 levels per level attempt this way. As with most RPG leveling schemes, the higher your level is, the more points you need to level, (To understand what is happening, note on the experience charts how much more experience you accumulate going from skill 50 to skill 51, than from skill 10 to skill 11, for example). So the points you accumulate with the Skeleton Key to gain a level are far in excess than those needed to gain a level at your lower (real) level. Retrieving those extra points, however, is mildly tricky.
- As you pick locks (or just raise tumblers) with the key, periodically check your skill statistics. Just as you are nearing the next Security level, remove the Skeleton Key from your inventory (the safest way to do this is to put the key in a container; if you drop the key on the floor, be sure to save first just in case the key falls through the floor).
- Continue picking the lock using a regular lockpick, but do not attempt to open the lock. You will immediately gain a skill level, and will continue to gain skill levels for each learning "success" (for example, every tumbler you successfully lift) using a regular lockpick, until all of the surplus experience gained while using the Skeleton Key has been exhausted, assuming you are of low enough level. So don't actually try to open the lock or use an auto-attempt. After dropping the Key, the extra points you obtained from being at a higher level remain internally in the game and are not added automatically. If you continue to use the Skeleton Key, those points are cleared at each level since the game assumes you are that higher level. If you don't drop the Key prior to leveling, all the added points from "learning" with the Key disappears forever. But you will have still gained at least one level – you simply missed the opportunity to rise 2 to 5 levels at that point by holding on to the Key.
- After you are no longer leveling with each "learning" success (i.e., you have exhausted your surplus experience lifting tumblers and the progress bar is not moving fast any more), pick up the Skeleton Key again and start working towards your next skill level, repeating the process. The extra experience points gained while leveling with the Key must be deliberately retrieved.
- This is a very fast and cheap way to level up Security regardless your Security level because: (1) you never buy lockpicks, (2) you don't waste time on save/reload cycles except briefly just at leveling-time, (3) lockpicking goes faster because your Security skill is 40 points higher, and (4) you gain at least two levels for every one you suffer through (if your start level is low).
- If you give Martin the Skeleton Key to complete the Blood of the Daedra quest, you may still have the +40 bonus to Security.
- This bug is fixed by the Unofficial Oblivion Patch.