Ultima Online Snooping - the two published numbers, and the thief play they enable

The two published numbers

In full, because this is the whole numeric record:

• 1 tile. uo.com’s procedure is to open the target’s paperdoll and double-click their backpack while standing within one tile of them. That is the range, and it is the skill’s defining constraint in PvP.
• 100 (Grandmaster). uo.com: “Grand Master Spies will never fail to snoop successfully, and therefore will never be revealed by the act.”

And what is not published:

• [!] The success chance at any skill below Grandmaster. Nothing between “you have the skill” and “you never fail” is quantified.
• [!] How much karma a snoop costs. uo.com states that it lowers karma, but not by how much, or how often.
• [!] The chance of being revealed on a failed snoop.
• [!] Any reuse delay between attempts. Stealing has a published ten-second figure; Snooping has nothing.
• [!] Whether the check on a sub-container is harder than on the top-level backpack. uo.com says checks occur again on sub-containers, not how they differ.
• [!] Any weight or item restriction on what Snooping can see. Stealing publishes weight limits; Snooping publishes none, which is not the same as there being none.

What it actually does

uo.com: the skill triggers “when you attempt to open a container belonging to someone other than yourself.” The procedure is the target’s paperdoll, then a double-click on their backpack, from inside one tile. Skill checks happen again when you open a sub-container inside the pack.

uo.com’s Stealing page states the dependency from the other side: “To target steal from players the character must have the skill ‘snooping’ in order to see into your victim’s backpack and select the target item.” In practice that makes Snooping a prerequisite for Stealing. It opens another character’s backpack, pack animals, and NPC backpacks.

There is one published exception to the whole “look in a pack” framing. uo.com states that a character cannot obtain the special items from Exodus Zealots without Snooping skill, despite the zealots having no backpack at all. That is the “one particular pvm encounter” in uo.com’s own description of the skill.

Success hides you, failure exposes you

uo.com: a successful snoop keeps the player hidden. A failed one displays “You notice (name) peeking into your belongings!” to nearby players and reveals a hidden character. Then the line that makes Grandmaster the target rather than a nice-to-have: “Grand Master Spies will never fail to snoop successfully, and therefore will never be revealed by the act.”

[!] The risk is not entirely settled. An unpublished claim holds that even a successful snoop carries a chance of being noticed — nearby players get the message, and a hidden snooper may be revealed. On uo.com’s account a Grandmaster is safe because they never fail; on the unpublished one success itself carries a notice chance. uo.com’s is the official statement.

Either way the interaction with Hiding is the same shape: uo.com lists Snooping among the things you may do while hidden, with the caveat that failure — “if insufficiently skilled” — reveals you. And because Stealth requires the hidden state, a failed snoop ends that too.

Not a crime, but it costs karma

This is the part that shapes thief play, and uo.com states it in one sentence worth quoting whole:

“Although snooping is typically looked upon as a negative act, you cannot be Guard Wacked for it, nor will you be flagged as a criminal, however it will lower your karma and you can not perform it in Trammel, with one notable exception.”

On the facet restriction, uo.com says you cannot do it in Trammel, with one notable exception — the exception being its own pack-animal training method, where you snoop an animal you released yourself. Put as a targeting rule: outside Felucca, you cannot snoop a player’s character or pet unless they are in your guild.

In PvP

uo.com calls it “essential for all pvp thieves”, and the reason is arithmetic rather than flavour.

• Random stealing from a player is close to worthless. The thing you want — a power scroll, a rare, an artifact — is one item among many in a full pack. Snooping is what turns a lottery into a choice.
• It is the safe half of the thief’s turn. Snooping is not a criminal act and cannot be guard-whacked. Stealing is a criminal act and, in a justice region, guards kill you for it. So the published play is to scout the pack in the bank, in the guard zone, at no risk, and commit to the actual steal only when the contents justify dying for them. That asymmetry is the core of PvP thief play, and it exists entirely because these are two separate skills with two different legal statuses.
• It makes you pay a tripled difficulty on purpose. uo.com’s Stealing formula uses a targeting factor of 1 for random and 3 for planned theft. Snooping is what lets you spend that 3× deliberately on something worth having instead of taking junk cheaply.
• One tile is the counter. The thief must stand in melee range of the target to snoop at all. A defender who keeps people out of that tile does not need Detecting Hidden to beat the skill.
• Grandmaster, not ninety-something. Per uo.com, GM removes the failure and therefore the reveal entirely, so a GM Spy can work from a hidden state indefinitely. Every point below 100 is a chance of the “peeking into your belongings” message going out to a bank full of people.
• Karma is the standing cost, which matters on any template keyed off it, and [!] its size is not published.
• Felucca only against players and their pets, unless they are in your own guild.

In PvM

One use, and it is a real one.

• Exodus Zealots. uo.com: without Snooping you cannot obtain their special items, even though they have no backpack. The Stealing page states the consequence from the other end — without Snooping, “only gold can be stolen”.
• Everything else in PvM does without it. Monsters with no accessible backpack are handled by random stealing, which also has the published advantage of taking heavier objects. If Exodus is not on your route, Snooping is not on your template.

Caps, stats and training

Primary stat Dex, secondary Int. Snooping has no Power Scrolls — it is absent from uo.com’s published Power Scroll list. It stops at 100, against the 720 total skill cap. Since uo.com’s never-fail statement is pinned to Grandmaster, 100 is both the cap and the goal. There is no Snooping mastery.

One item carries Snooping skill points: the Burglar’s Bandana, and it is the only one. Both Alacrity and Transcendence scrolls cover the skill.

uo.com publishes two training routes:

Facet	Method
Trammel (karma-neutral)	Buy a pack animal, buy a crook from an NPC Blacksmith or Weaponsmith, release the animal, use the crook with Herding, then open the animal’s backpack. This is uo.com’s “one notable exception” to the rule that Snooping cannot be performed in Trammel — you are snooping an animal you released yourself.
Felucca	Snoop static Escort NPCs, or hire NPCs for a fee — blue beggars, thieves, bards, fighters, peasants.

In practice: find a pack animal — an unattended one is best, because it stays put — and double-click it over and over, or to work NPCs outside guard zones.

Underneath either, the Guaranteed Gain System awards a mandatory 0.1 when nothing has been gained inside your bracket’s window, and a Scroll of Alacrity raises each check to 0.2–0.5 for 15 minutes.

What is not published

• [!] The success chance at any skill value below Grandmaster.
• [!] How much karma a snoop costs.
• [!] The chance of being revealed on a failed snoop.
• [!] Any reuse delay between snoop attempts.
• [!] Whether a sub-container check is harder than the backpack check.
• [!] Any weight or item restriction on what Snooping can see.
• [!] A resolution between uo.com’s “Grand Master Spies will never fail” and the unpublished claim that even a successful snoop can be noticed.

Where these come from

uo.com Snooping · uo.com Stealing · uo.com Hiding · uo.com Skills, Stats & Attributes · uo.com Scrolls of Power · uo.com Scrolls of Transcendence · uo.com Skill Masteries · uo.com Skill Gain Systems. Everything here is from uo.com or the game itself; anything uo.com does not publish is marked [!] as unpublished where it appears.