Your First Game System

This tutorial builds a small but complete game system from scratch: a system file, one faction catalogue, a unit with options and points, and force constraints. At the end you load it in the builder and see it work.

1. Create the system

Open the NR Data Editor, select Create System, and enter a name.

The system and its catalogues live together as files in one folder, your working folder (set it with Set Working Folder if the editor asks). Remember where it is: testing in the builder and publishing with git both point at this same folder later.

2. Add factions

Create a new catalogue for each faction available in your game. Each catalogue becomes a choice in the builder's faction selector.

3. Add forces

Open the game system (the file with the two-cogs icon). Force Entries should contain an entry named "Default Force". If it doesn't, right click Force Entries and select Force to create one.

4. Add categories

In Category Entries, create the top-level categories your units sort into, for example "Troops", "Characters", "Monsters".

5. Make categories available in the force

Back in Force Entries, right click the force and select Category. In the right-hand menu, pick one of your categories under Link > Target. Units with that category become available as choices within that force.

6. Create units

Right click Root Selection Entries and select Entry to add a unit, and set its Type to unit.

Then right click the unit and add a child Entry for each distinct kind of model in it, with Type set to model; even a single-model unit gets a model entry. The models are what the builder counts, prices, and tracks, and later steps put the size constraint and the stat line on them. The Type field is not cosmetic; see entry types.

Many systems define the unit under Shared Selection Entries and then add a link to it under Root Selection Entries, so the same unit can be reused. There is a shortcut: right-click a node and choose Move To. Moving an entry from Root into Shared Selection Entries leaves a link behind for you. For a first system you can create it directly in root; see Links & Shared Entries for why sharing helps later.

7. Set the unit's primary category

New units show under "Uncategorized" by default. Add one of the categories you made available in the force, then mark it primary. The primary category is what groups the unit in the builder. An entry has exactly one primary category; other categories are used for logic and datasheet display.

8. Add options

Options are the choices a player makes on the unit, such as a weapon or an upgrade. Add a child entry under the unit for each option.

For a "pick one of these" choice, add a selection group under the unit, set it to min 1, max 1, and put the choices inside it. Name the group after the choice, for example "Weapon". See Weapon options for the full pattern.

9. Add constraints

Constraints limit how many of something can be taken. On an entry or group, add a constraint and set its min and max.

• Unit size: a min/max in parent constraint on the model entry.
• Pick exactly one: min 1, max 1 on a selection group.
• A default so a fresh unit is legal: set the defaultAmount field on the entry that should start selected, rather than forcing it with a constraint.

See Scope & Context for what a constraint counts.

10. Add points costs

Points need a cost type. In the game system, under Cost Types, create one named pts (or Points). This is the currency the whole system uses. Its name is what players see next to every cost, so short is usual, and it names the pts Limit field used in the next step.

Set a cost on an entry by adding a cost of that type and a value. To make a unit cost more as it grows, price the models rather than the unit; see Points that scale per model.

To give the game a default army size, set a defaultCostLimit on the cost type; it prefills the cost limit when a player creates a roster (they can still change it).

11. Add force limits

Limits on how much of each category an army may take live on the force's category links. Select a category under the force and add a constraint, such as max 6 selections.

Percentage limits like "max 50% of a category" are common. Base the percentage on the cost limit (the game size) by setting the field to pts Limit, not on the points currently spent. See Army-wide limits.

12. Add profiles

Profiles are the stat blocks. They need a profile type first. In the game system, under Profile Types, create one (for example "Unit") and add its characteristics (Move, Save, and so on).

Then add a profile of that type to the entry it describes and fill in the characteristics. Put the stat line on the model, not the unit: where a unit has model entries, each model carries its own stats, even though the profile type is often named "Unit". A weapon's profile goes on the weapon. A profile sits directly on the unit only when the unit has no separate model entries beneath it. See Put each profile on the entry it describes.

13. Add rules

Most units carry rules text as well as stats. Right click the unit (or the model) and add a Rule, then write the rule text in its description. Text renders Markdown and auto-links the names of other rules; see Profiles & Rules. For a rule several units share, define it once and reference it with an info link instead of copying the text.

14. Test it in the builder

Load the system in NewRecruit and build a list to check it behaves. The fast way is the hot-reload loop from Installing the Tools: Add from folder on a Chromium browser, pointed at your working folder.

If a unit doesn't show up, work through the Troubleshooting checklist.

When it works, publish it so players can load it from GitHub.