Crusader Kings III — Achievement Walkthrough

Holy Orders are founded via the religion/Head of Faith mechanics — you generally need to be (or be close to) the Head of Faith of an organized religion, or hold the relevant authority, and meet the piety/requirements to create one and grant it land. As a powerful ruler of an organized faith, use the create-Holy-Order option and endow it with a county. Being independent with high Piety and an organized faith is the smoothest route.

Marry a young, fertile spouse (high Fertility, the Fecund trait helps enormously) and keep trying for children. Boost fertility with the relevant traits, the Carnalist perk, and a healthy ruler. Avoid your children dying young (good guardians, avoid wars/plague exposure). Ten ALIVE simultaneously is the bar, so a long marriage to a Fecund partner does it.

Secrets are discovered by your spymaster's 'Find Secrets' task and via events. Assign a high-Intrigue spymaster to find secrets at a target court, and use the Intrigue lifestyle (Secrets-focused perks) to uncover more. Hold onto them (don't expose/blackmail them all away) until you have ten at once. A big neighbouring court gives your spymaster plenty to dig up.

Your whole dynasty (not just your house) counts. Marry off relatives matrilineally/patrilineally to keep them in the dynasty, encourage big families, and don't let branches die out. Over a few generations with healthy, fertile members the count climbs. Playing a faith/culture that allows many wives (so more children per generation) accelerates this hugely.

Each Lifestyle (Diplomacy, Martial, etc.) has three perk trees. You earn lifestyle XP over time based on your focus. To buy every perk in all three trees of one Lifestyle you need a long-lived ruler — boost lifestyle XP with the matching focus, high relevant skill, events, and the 'gain experience' decisions. Pick a young ruler with a high stat in one lifestyle and live long; education traits and XP boosts speed it up. Completing all 3 trees of any single lifestyle unlocks it.

Dynasty Legacies are bought with Renown (earned passively by your dynasty's prestige/size). Pick one legacy track (e.g., Blood, Glory, Kin) and save Renown to buy all five of its perks. Grow your dynasty and hold high-tier titles to pump Renown, then dump it all into one track. Any one fully-completed track earns this.

Pick a Count with room to grow (a fragmented region like Ireland, or a Count near a weak liege). The path: secure your county, press de jure claims on neighbours to become a Duke, then a King, then accumulate enough kingdoms (or a de jure empire's titles) to create an Empire title. Keys: a stable succession (avoid splitting your realm — switch to a single-heir succession law like Primogeniture when possible), grow your domain/army, and use claims, fabrications, and the occasional murder to expand faster than your neighbours. Restoring/creating any empire title completes it.

You need enough Piety and to be eligible to reform/create a faith (usually as an independent ruler, sometimes requiring being the faith's Head or having a Religious authority). Accumulate Piety, open the religion screen, and Create a New Faith — pick its tenets and doctrines. Save up Piety as a devout ruler, then split off your own faith.

Start a Murder scheme targeting your spouse. Boost success with a high-Intrigue character, recruited agents, and the Intrigue (Schemer) perks; reduce risk so you aren't discovered. Let the scheme succeed. A Devious/high-Intrigue ruler with several agents makes spousal murder reliable.

Duchy Buildings are special structures you can build in a duchy capital you personally hold (you must hold the duchy title). Build one (e.g., a military or economic duchy building) and upgrade it to its maximum level — each tier costs gold and time and may need realm innovations. Hold the duchy title, have a strong treasury, and pour gold into one duchy building until it's maxed.

The Claim Throne (hostile) scheme lets you press toward usurping a title via intrigue. You need to be a vassal/claimant in the right position; start the scheme against the title-holder, build scheme power with agents, and let it succeed. A high-Intrigue character with supportive agents makes success likely. Set it up where you have a claim and run it to completion.

You must hold the required territory to form the Roman Empire decision: control Rome, Constantinople (Byzantion), and the other core de jure regions (roughly Italy, the Byzantine heartland, and surrounding kingdoms), plus the prestige/level and usually a specific faith/culture or the renown. Easiest as the Byzantine Empire (start 867 or 1066) — you already hold half of it; expand west to take Italy and Rome, hold the required duchies, then take the 'Restore the Roman Empire' decision. Expect many wars and a strong, undivided realm.

Hooks come from discovering secrets, winning certain events, or favors. A 'strong' hook (reusable) is the better tier. Discover damaging secrets on three of your direct vassals (spymaster + intrigue), then convert/obtain strong hooks on each. Use your spymaster to find vassal secrets, then leverage them into strong hooks on three different direct vassals at once.

Inbreeding chance rises sharply when parents are closely related. Marry within close family across generations (where your faith allows incestuous unions — e.g., certain reformed/pagan faiths, or use the relevant tenets). Have children from closely-related couples and eventually one is born Inbred. Faiths with Divine Marriage / consanguinity acceptance make this far easier and avoid the tyranny/penalties.

A joke achievement. Once you hold any Empire-tier title, get the 'naked' state — this comes from a specific event/decision or trait (e.g., certain stress/whim events, or the relevant decision). The simplest reliable route is triggering an event that strips your clothes, or using the decision/whim while you're an Emperor. Hold an empire, then get naked via the available event/decision.

Use the Seduce scheme repeatedly. Take the Seducer perks (Intrigue lifestyle), have high Intrigue/Attraction (the Comely/Beautiful traits, good appearance), and target receptive characters (compatible sexuality, low resistance). Run seduction schemes back-to-back across your life until ten succeed. The Seduction Scheme Power perks make each far more likely.