Crusader Kings III: By God Alone puts the papacy in your hands

Paradox Interactive has released By God Alone, the latest core expansion for Crusader Kings III, alongside the free 1.20.0 “Crozier” update. Both arrived on Steam on 30 September, and the expansion costs £16.99 in the UK either on its own or as part of the Chapter V season pass.

What the Christian Church situation does

The centrepiece is a map-wide Situation covering all of Christendom. Every Christian ruler at county tier or above takes part, and all participants share the same Chapter, the same modifiers and the same Great Schism progress. Rulers are sorted into six groups — the Main Power and Secondary Powers, each split into clerical and secular, plus heretics in those same two camps — so the church and the crown are modelled as separate blocs with separate interests.

It works through seven chapters: Fragile Unity, Saeculum Obscurum, Conversion, Reform, Investiture Controversy, Crusade and Concord. Each is typed as Stability, Zeal, Instability or Crisis, and each applies its own religion, subject, diplomacy and warfare modifiers differently to each group. A Crisis chapter can tip into the Great Schism once schism progress passes its threshold.

Play as a bishop, an archbishop or the Pope

The expansion's headline pitch is that theocracies are playable for the first time. You can lead a bishopric, or take the papal throne in Rome and run the church treasury, its own government type and its regional archdioceses. Catholic Christendom gets a College of Cardinals with a papabili scale, where the election turns on the contest between pious ascetics, powerful magnates and popular favourites.

Secular monarchs are not shut out of that fight either. They can defy the Holy See by raising an antipope, and Paradox's own art notes describe the design they started from: the finished key art shows “secular rulers puppeteering the people around the church to bend it in their favor”. On the game's published screenshots that loop is explicit, with clerical ruler puppets, realm priest puppets and secular ruler puppets all able to be leaned on to excommunicate a rival or press a claim.

Saints, appointments and the road to the Schism

A canonisation system lets landed rulers put a departed ancestor forward to be recognised as a saint. It needs the faith's rite to permit or make core the veneration of saints, and the burial itself has to happen in a cathedral inside your realm or at one of its holy sites, with each province able to hold only one saint. Both the gold and piety costs rise with the number of saints your dynasty has already produced, there is a 25-year cooldown on the decision, and where a faith has a Head of Faith that figure decides the petition — Chalcedonianism, which has none, creates the saint on the spot.

Christian faiths also start on a new conditional clerical appointment doctrine, under which neither the crown nor the clergy needs permission to appoint clergymen in its jurisdictions. As a secular ruler you can simply install a court chaplain or an archbishop yourself, paying for it in opinion, in a “Meddling in Clerical Appointments” modifier and in catalysts that drag the situation towards the Investiture Controversy and Saeculum Obscurum chapters. The other catalysts are simony, clerical marriage and children, murdered prelates, cardinal appointments, holy wars, excommunications, lost and reclaimed holy sites, new rites, antipopes, heresy outbreaks, ecumenical councils, consecrated kingdoms and great project contributions. A Guide the Christian Church decision, available once a decade, fires a catalyst of your choosing — with four times the effect if you hold the Head of Faith title.

What the free Crozier update changes

The 1.20.0 “Crozier” update ships free to everyone and rebuilds monastic and knightly orders, adds dynamic holy sites with relic veneration and introduces great projects. It also carries a round of performance work: on Paradox's low-spec reference machine the time to reach the main menu fell from 84 seconds to 16, video memory in one test scene dropped by between a third and a half depending on texture quality, and system memory a decade into a campaign came down by roughly a sixth. The studio's own dev diary is careful to say those numbers were still moving at the time of writing.

Our opinion

Paradox's strongest expansions hand players a system nobody else is simulating, and a College of Cardinals where piety, wealth and popularity are three separate currencies is precisely that. The risk sits in the catalysts. By God Alone publishes the full list of levers that nudge the Christian Church between chapters, which is good for transparency, but a public list of fifteen named triggers sitting behind a visible threshold is a system the community will optimise inside a fortnight — and a Great Schism you can schedule stops being something to fear.

If the politics hold up, though, the expansion earns its £16.99. Making bishops appointable, excommunicable and bribable finally gives the medieval church the weight it carried in the period, rather than the piety counter it has been since 2020. Handing the order reworks and the performance gains to the free Crozier update, while the church itself stays paid, is also a more generous split than Paradox has managed in recent years.