Overview
Lockpicks improve your ability to pick a lock. In game, lockpicks appear as a set of lock picks or alternatively a strange set of lockpicks if they contain any improvement (see below).
They can be puchased in the Dwarven Homes in the Blue Mountains (shop is accessible to citizens/dwarves only) or in Tharbad's traveller's store. They may also sometimes be found at other grocers / travelers shops if they got sold there by a player and can also be found on certain mobs.
You can use them either by holding them, or wearing them on your belt, or on a keyring that is worn on your wrist. If worn in any such way, they will automatically be applied whenever you try to pick a lock.
Spoiler
Lockpicks add +25% pick skill and an additional +3% per upgrade (these exact numbers needs to be confirmed). This is in addition to any pick skill practiced.
Improvements
Your lockpicks can be improved to work faster and better. Around Arda you will find people who can help you improve your lockpicks, these are the ones found so far. In most cases you can ask about lockpicks, and the mobile will begin talking. Once a set of lockpicks has been improved, a new line will be added to their description. To view this description - examine lockpicks.
Spoiler
Assassin Guildmaster
Price: 15 gold.
Description: Two of the lockpicks have shallow notches on them.
Master Assassin
The Master Assassin will improve lockpicks as a reward to the person who kills Malardil and brings the silver key to him. Just approach the Master Assassin with the key in your inventory, give him key after he asks for it, and remember to stay cool. Remember that you must be neither invisible nor sneaking while passing doorguards and entering MA. His reward is random: he always gives you 3 gold, then sometimes he gives you small pouch of paralyse, sometimes offers you picks upgrade (give him picks after that). Btw it is also very easy to steal his own picks after getting your picks upgrade or pouch 😉 Like 80% steal needed.
Price: silver key
Description: A couple lockpicks have a small bump near the tip.
Angdil
Price: an evil artifact weapon (HBM, ElfHewer, Morgul Blade, HFS, Black Many-Tailed Whip) or Morgul Blade's sheath.
Description: The edges of most picks have been carefully sharpened.
Dwarven Locksmith
This upgrade is only available to dwarves. You must bring a piece of mithril to the lockpick selling Dwarf in Blue Mountains.
Price: pure Truesilver: a piece of mithril (silvery metal), mithril key (Muranog cabinet) or fine chain piece. White chain doesn't fit!
Description: The lockpicks are extremely well tempered.
Kraksh the Orcish Scout Guildmaster
This upgrade is only available to orcs.
Price: a precious jewel (corberyl+ works, opal- doesn't, didn't tested topaz).
Description: There is a strange lockpick, with a sharp protrusion on one side.
Grey Cloaked Man
This upgrade is only available to Black Numenoreans.
Price: oak staff from a slain whitie.
Description: The lockpicks feel oddly light in your hand.
Half-elven cut-throat
To get upgrade, give lockpicks to him - no messages like "he starts working on picks" or whatsoever. He does, and (btw) immediately! Kill him (or steal) to get picks back. It's better to give him tons of picks at one time - just to save yourself from excess trips to his hideout.
Price: Free.
Description: Several of the picks have long, smooth grooves along their length.
Saruman
Price: Give an item of power to Saruman (the pick upgrade is random chosen from a set of possible rewards). Yerik gives you NEW set of picks with his upgrade instead of upgrading your existing set. Usually claymore should be fine to get picks.
Description: A finely shaped lockpick has been engraved with a white hand.
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