Research guide: routes, prerequisites and doctrines

When research stops

First distinguish an empty desk from slow progress. If nothing is queued, select the next destination or use the available next-idea shortcut. If a technology is active but advancing slowly, inspect Knowledge income and its cost. A large target can look motionless when a small economy is trying to fund it.

Check the selected target’s prerequisites and doctrine group. Researching an exclusive alternative prevents the other member of that group from being taken later. More Knowledge does not remove that lock.

The research panel can be dragged to move the board and zoomed with the scroll wheel. Look at the current research display as well as the selected technology: inspecting a completed node is not proof that the active desk is empty.

Pick a route around a problem

Unlocks are not purchases. Researching Irrigation still leaves you needing a level-2 eligible city and construction resources for Irrigation Works. Researching cavalry still leaves you needing a Barracks and the resources to raise the units. Use the building table alongside a research plan.

Budget Knowledge before choosing a route

The unmodified technology costs by tier are 38, 160, 520, 1,500, 3,000 and 6,000 Knowledge. A route may pass through more than one branch, so the cost of its final node is not the cost of reaching it.

Crop Rotation plus Irrigation costs 198 base Knowledge. Adding Public Granaries brings that route to 718. Royal Chancery and other effects can change actual costs, while existing research progress changes what remains to be paid. Knowledge production determines time; a fixed “research this at minute two” instruction ignores those conditions.

Doctrine tradeoffs

There are seven exclusive pairs. Make each choice as part of a kingdom plan rather than treating both options as upgrades you will eventually collect.

The military pair deserves particular care. Professional Officers does not make all siege recruitment impossible. Royal Siegecraft is a separate technology requiring Advanced Masonry and Iron Weapons, and the siege unit definition accepts either Siege Engineering or Royal Siegecraft. Choosing the field-army doctrine changes your siege route; it does not erase the engineering branch.

Before choosing either military route, compare the capital’s three finishing conditions. The technology decision should support the operation you intend to carry out.

Plan around what the realm can use now

An economy that cannot afford a Barracks gains little immediate pressure from a troop unlock. A well-funded army that cannot complete a capital siege needs a finishing plan, not another unrelated economic technology. Before each route, name the action it enables: build a specific structure, improve a specific income, support a frontier or prepare an attack.

If you cannot name that action, pause the plan and inspect the current bottleneck. A deep target can be correct, but the kingdom still has to survive the prerequisites. The advanced strategy guide shows how doctrine choices should line up with city roles and military goals.