Duckov Codex ​

What it helps you do ​

The Codex records defeated bosses so you can choose an opponent you have not beaten, or revisit a familiar fight to improve your time. A first kill unlocks an entry; repeat kills update its count and best time. Completing the collection does not require repeatedly farming the same boss.

Opening the book ​

• Buy a Duckov Codex from the normal base merchant. Its base price is 4,000, with one copy per restock.
• Right-click it in your inventory. Reading consumes neither the book nor durability.
• The book opens the viewer. Kills and achievements are recorded without owning it, so you can start collecting first.
• If you lose it, wait for the shop's normal restock to buy another. Progress belongs to your save slot, not the book.

Choosing your next opponent ​

• The top bar shows collected entries and the current catalog size, with marks at 10, 20 and completion.
• Switch views with the All / Missing segments at the top: Missing lists only undefeated bosses and shows how many are left; All restores the full list. This display filter does not change achievement requirements.
• The whole catalog is laid out in one pass - there are no page buttons, just scroll. Recorded cards show names, kills and best times; unrecorded ones show only a silhouette and the name.
• Click a card for its category, total kills, fastest kill, first-seen date and first-seen location. Locked cards still show names and category; unrecorded stats show a dash.
• ESC closes the details first, then the Codex. Changing the game language updates the interface and boss names that have a current translation.

Pick a missing entry, make sure it is enabled in the Boss Filter, then head into the arena and return after the fight to check your record. Revisit familiar opponents when you want to improve your time.

Which bosses appear ​

• Official bosses: every official boss has a slot. Even one you disabled in the Boss Filter, or one you have never met, stays in the book as a locked card so you can see what is still missing. Re-enable it in the Boss Filter before hunting it; Arena and Infinite Hell pick from the enabled pool randomly, so a boss is never guaranteed in the next wave.
• Official elites: high-health opponents the game does not mark as bosses (the red and blue captains, Ultraman, the Ghost and so on). They are not part of the official boss roster; their detail page reads "Official elite".
• Three custom bosses: Dragon Descendant, Skyburner Dragon Lord and Phantom Witch. These always remain in the catalog. Re-enable them in the Boss Filter if you disabled them.
• Five zombie bosses: Titan, Hunter, Splitter, Shielder and Corruptor. Zombie Mode has a boss wave every five waves, with kinds rotating as you advance.
• Additional defeated bosses: qualifying kills outside the catalog are kept as historical records, such as the campaign's final Champion's Shadow. Undiscovered hidden opponents do not add locked entries in advance.

Filtering out a collected boss never removes its record. Names use the current translation when available, otherwise the historical name.

Kill credit and timing ​

• The fatal blow must be attributed to the main player. Ordinary pets, PetNest companions and environmental finishing blows do not count. Player deaths, friendly targets and base demonstration characters are excluded.
• Faction War exception: that mode attributes kills by your hired bosses to you, so those kills can count.
• The Black Market Duck Cup is excluded throughout. Qualifying kills in other modes and vanilla raids can count.
• Best time measures from your first observed damaging hit until death, using game time. Pausing adds no time; dodging, reloading and healing during the fight do.
• A one-hit kill or missing starting observation records the kill without inventing a duration, shown as —. A valid starting hit and kill observed within the same frame display <0.1s.
• First-kill date and mode are set once. All modes share one best-time record per boss; this is not a leaderboard for equal difficulty.

Milestone rewards ​

The existing achievement system unlocks and pays these once per save slot. Owning or carrying the book is unnecessary:

• First entry → 50,000
• 10 different entries → 150,000
• 20 different entries → 400,000
• Complete the current catalog → 1,000,000
• Inside Ten Seconds: one boss kill with a valid measured time of 10 seconds or less → 200,000

Completion requires defeating every boss in the current catalog. Extra historical entries cannot substitute for a missing boss. The official portion is every official boss and does not shrink when you disable some in the Boss Filter - disabling only stops them spawning this run, the slot stays in the book. The three custom bosses and five zombie kinds remain required. Expanding the catalog does not revoke achievements already earned.

Saving and portraits ​

The Codex is enabled by default, with separate progress for each save slot. Kills first enter the save queue; returning to base and the normal save flow write them to disk. Forcing the process to close can lose records that have not yet been saved.

If the panel reports that recording is unavailable, reload and check again. Rejected updates do not appear as earned progress, and unreadable saved data is not overwritten with an empty collection.

If a dedicated portrait is missing, a card uses an official icon or a name initial. Names, category, collection and rewards remain available.