Castle Blackthorn Dungeon

Castle Blackthorn Dungeon is the dungeon located beneath Castle Blackthorn on both Felucca and Trammel facets, introduced with Publish 85 (2014). It is one of UO's most distinctive modern dungeons because of its two-part structure: a Catacombs section spreading out like a star from the entrance with traditional dungeon spawn, and a rift-in-space-time section where sections of nine surface cities are replicated and suffer random invasions by powerful creatures. The rewards — Artifacts Bearing the Crest of Minax, exchanged with the Agent of the Crown for the prestigious Blackthorn Artifacts — anchor the dungeon as a major endgame content destination, and the dungeon-points + Luck-modified drop system (similar to the Doom Gauntlet) ensures consistent rewards for time spent.

Location and entrance

• Beneath Castle Blackthorn in Britain — both Felucca and Trammel facets.
• Entry is through the castle, not by direct rune-mark or recall (see Specific Game Mechanics below).

Specific Game Mechanics — the castle restrictions

Castle Blackthorn was designed for roleplaying scenarios, and several restrictions apply:

To recover pets after entering the dungeon: a hitching post is located just past the base of the stairs. Say "claim list" for a list of all stabled pets.

A trash bin is located at the base of the stairs — any path-blocking objects placed on the dungeon floor are removed to this bin.

Anti-Hide / Anti-AFK rules

• Characters who hide in the dungeon are auto-revealed after a short interval.
• Characters who remain in one place for too long are auto-teleported to another location in the dungeon — usually in the middle of a poisonous gas cloud surrounded by hostile creatures that immediately attack. Fun times!

The Catacombs

A star-shaped catacomb spreads from the entrance. Three paths radiate:

The catacombs system allows characters of almost all skill levels to find appropriate combat. Every skill level has the chance to acquire Minax artifacts — and therefore the more powerful Blackthorn Artifacts.

(Note: As of 2022, the catacombs are 'turned off' and not actively spawning monsters. The rift invasions are still active.)

What to fight — the dungeon-points proxy

A common question: "What should I fight to maximize my time?" The answer involves the dungeon-points system:

Use gold-drop value as a proxy for "dungeon points."

After 50+ Minax drops from the catacombs:

With ~2,000 Luck, an artifact drops at approximately 45,000 gold ± 15,000 in cumulative kills. That works out to:

• ~37 Balrons for one drop, OR
• ~300 Evil Mages, OR
• ~1,300 Skeletons.

The answer depends on your kill speed: - 8 Evil Mages at 150g/each = 1,200 points; one Balron at 1,250 = ~equivalent. If you can kill 8 Evil Mages in the time it takes to kill 1 Balron, they tie. - Over time, ~37 Balrons may be killable faster than ~300 Evil Mages. - Just recognize that Luck plays a factor and gold-drop is a reliable proxy for dungeon points.

The Invasions — space-time rifts

The dungeon's second part is a rift in space-time containing sections of nine surface cities:

An invasion is always occurring in one of the rifts — but which rift is random.

Invasion structure

Each invasion has:

Wave mechanic

1. Wave begins. Captains invulnerable (yellow), minions vulnerable (red).
2. Defeat all minions for a particular Captain → that Captain becomes vulnerable (red).
3. Defeat all Captains and minions for the wave → the lighthouse beacon becomes vulnerable.
4. Attack the beacon → it takes tremendous damage before damage is dealt; once enough damage is dealt, a new wave starts.
5. After the final wave is killed, the beacon is destroyed, freeing the rift of the invasion.

Invasion rewards

• Captains have the greatest chance of awarding a Minax artifact (the highest-value spawn).
• Minions can also award artifacts.
• Destruction of the Lighthouse Beacon after the final wave can also award a Minax artifact.

The reward chain — Minax artifacts → Blackthorn artifacts

Every creature killed in the dungeon (catacombs OR invasion) has a chance to drop "Artifacts Bearing the Crest of Minax" directly into the player's pack. The Agent of the Crown, located within Castle Blackthorn at the head of the stairs leading into Castle Blackthorn Dungeon, exchanges Minax artifacts for Blackthorn Artifacts.

The dungeon-points system

The drop mechanic is identical to the Doom Gauntlet approach:

1. Each creature kill awards dungeon points (proportional to creature difficulty / gold-drop).
2. When enough points accumulate, an artifact is bestowed on the character.
3. The dungeon-point counter resets after each artifact drop.
4. The Luck statistic factors into the drop rate.

Theoretically, any creature can drop an artifact thanks to the RNG, but the points system ensures a reward for time spent — the gauntlet pattern that became the modern UO standard.

Notable Blackthorn Artifacts

The Blackthorn Artifacts comprise some of the strongest endgame gear:

• Coif of Vesper Sentinels
• Cuffs of the Archmage
• Robe of the Equinox
• Robe of the Wisps
• Rune Beetle Carapace
• Stormgrip (also a ToT artifact)
• Bracelet of Ash
• Inquisitor's Resolve
• Many others — full list at the in-game Agent of the Crown's exchange menu.

See also

• Lord_Blackthorn — King of Britannia, namesake of the castle
• Minax — namesake of the artifacts
• Doom — sister gauntlet system; dungeon-points pattern reference
• Publish_85 — the introducing publish
• Britannia — the surface kingdom
• Castle_Blackthorn — the surface castle
• Agent_of_the_Crown — the exchange NPC
• Luck — affects drop rate