Lockpick

Lockpicks are used to open chests that are locked in both normal and hard mode. While they are optional in normal mode, every Locked Chest in hard mode must be opened using a lockpick. In the expansion Eye of the North all Locked Chests require a lockpick.

Use
Unlike keys, lockpicks have a potentially infinite number of uses. They do, however, have a percent chance to break depending on certain factors. Once broken, the lockpick is destroyed and will disappear from the inventory. Successfully retaining a lockpick earns 250 points towards the Lucky title while breaking one adds 2.5 points for every 1% retention rate towards the Unlucky title.

Acquisition

 * Loot from mobs in hard mode in all games
 * Loot from the Zaishen Chest
 * Loot from the Chest of Woe and Underworld Chest in hard mode
 * Loot from mobs in normal mode in Eye of The North
 * Loot from Hidden Treasures (particularly in hard mode)
 * Loot from the Chest of Burrows
 * Purchased from any normal merchant for except for those in pre-Searing Ascalon
 * Purchased from a faction merchant for
 * Purchased from Pohke for 2 and
 * Reward from Royal Gift (1-5 lockpicks)
 * Reward from some quests in Eye of the North

Statistics
The base chance RR of retaining a lockpick upon opening a chest is determined by the following formula:


 * RR = ( Level / 2 + 3 * Treasure Hunter rank + 2 * Lucky rank ) / 100

A lockpick bonus will also be given on top of the inherent bonus to any normal chest, depending on the price of the key. This is to compensate for the money one would save in the long run when using keys rather than lockpicks in hard mode. The following tables illustrate the inherent lockpick retention based on titles and the bonus lockpick retention based on the type of chest in normal mode at level 20:


 * For example, you have a 40% retention rate (assuming rank 0 treasure hunter and lucky) for normal mode Eye of the North chests (i.e. 10% inherent + 30% bonus because EotN chests count as 600g chests).
 * If your retention rate is RR, then with one lockpick on average you will be able to open 1/(1-RR) chests.

Dialogue
The following messages appear for the user when they attempt to open a chest with a lockpick:

Opening a chest in Normal mode while you have both a key and a lockpick in your inventory:
 * Would you like to use a(n) [key name] or a lockpick to unlock the [chest name]? You have a X% chance to retain the lockpick.

Opening a chest in Any mode while you only have a lockpick in your inventory:
 * Would you like to use a lockpick to unlock the [chest name]? You have a X% chance to retain the lockpick.

Opening a chest in Hard mode without a lockpick:
 * This chest is locked. You must use a lockpick to open it.

Lockpicks vs Keys
If a character has no ranks in the Lucky title track or the Treasure Hunter title track, then it is almost always more cost-effective to use keys instead of a lockpick to open chests. However, by advancing those title tracks, the lockpick retention rate can increase to the point where it is more cost-effective to use a lockpick. The following tables show the inherent lockpick retention rate necessary for lockpicks to be cost-effective, first with the NPC merchant price of lockpicks, and second with the common player price.


 * align="center" | Based on 1 250  lockpicks. (Typical price for buying them from players in-game.)


 * - align="center" valign="top"
 * Key cost || Base Rate
 * - align="center" valign="top"
 * 50 ||   41%
 * - align="center" valign="top"
 * 80 ||   40%
 * - align="center" valign="top"
 * 200 ||  34%
 * - align="center" valign="top"
 * 300 ||  31%
 * - align="center" valign="top"
 * 450 ||  29%
 * - align="center" valign="top"
 * 600 ||  22%
 * - align="center" valign="top"
 * 750 ||  15%
 * - align="center" valign="top"
 * 1 250  || 0%
 * }
 * }
 * Base Rate is the Inherent Lockpick Retention rate (see Statistics, above) necessary for lockpicks to be as cost-effective as keys.
 * The values represent the point at which a single lockpick will open as many chests as 1 500  (merchant price) or 1  250  (common player price) worth of the corresponding keys.
 * For each given type of key:
 * If your inherent retention rate is less than the Base Rate, using keys will be cheaper.
 * If your inherent retention rate is equal to the Base Rate, using keys or lockpicks will cost you as much.
 * If your inherent retention rate is greater than the Base Rate, using lockpicks will be cheaper.
 * Please note that these boards only refer to the choosing between keys and lockpicks concerning which is cheaper and when.