Building a Warhammer 40k army means turning a pile of models into a legal, playable force with a plan behind it. The rules for doing that have shifted a lot in recent editions, and getting the basics right saves you cash and headaches.
What army building actually involves
It’s three things at once: collecting models you like, writing a list that fits a points limit, and making sure the units actually support each other on the table.
Beginners often stop at step one, buying whatever looks coolest. That’s fine if you’re here purely for the hobby side, but a list that plays well needs a purpose. It has to score objectives, threaten the enemy, and survive return fire.
Pick a faction, then a detachment
Your faction choice sets your Faction keyword and your core army rule. Pick something you genuinely like the look of, more than whatever’s winning tournaments this month, because you’ll be painting and playing it for years.
Then you choose a Detachment, which is a single set of rules for the whole army. It hands you extra Stratagems, Enhancements, and often a special ability. In the current edition, detachments are usually not tied to a paint scheme, so your custom Chapter can run the same rules as the poster boys.
- Faction: your army’s identity and army-wide rule.
- Detachment: the extra rules layer you build around.
- Enhancements: upgrades for Characters (or, in newer rules, sometimes units).
- Stratagems: command points spent mid-game for tricks and boosts.
Choose your game size first
Decide how big you’re playing before you buy anything. 500-point games are possible, but the Core Rules are tuned for larger forces. The three standard sizes are Incursion at 1,000 points, Strike Force at 2,000, and Onslaught at 3,000.
In the newer system, bigger games also give you more Detachment Points to spend on stacking detachments, plus higher Enhancement and unit limits. Power Levels are gone, so points are the only currency now.
| Battle size | Points | Detachment Points | Enhancement limit | Unit limit |
|---|---|---|---|---|
| Incursion | 1,000 | 2 | 2 | 2 |
| Strike Force | 2,000 | 3 | 4 | 3 |
Fill roles, then chase synergy
A balanced list covers the jobs: something to hold objectives, something to kill armour, something fast, and something to anchor your line. You don’t need a rigid template, but you do need answers to those problems.
Synergy beats raw power. A unit that buffs three others is usually worth more than a lone beatstick, and that’s exactly why detachments matter. Build around a theme, like a stealth-focused Phobos force, and the whole army gets sharper.
Grow it without wasting money
Buy in stages. Start with a combat patrol or a starter box, play small games, and let your list tell you what’s missing. Rushing to 2,000 points usually means buying models you’ll never field.
Once your core is solid, add units that patch weaknesses rather than duplicates of what you already own. That’s how a casual collection turns into something genuinely competitive.
Key facts
- Standard battle sizes are Incursion (1,000), Strike Force (2,000), and Onslaught (3,000) points.
- Power Levels have been removed; points are now the only way to size an army.
- Detachments give your whole force extra Stratagems, Enhancements, and abilities.
- Newer rules add Detachment Points, letting you combine several detachments in bigger games.
- Unit limits are doubled for Battleline units, so troops still have a place.
FAQ
How many points should a beginner army be?
Start at 500 to 1,000 points. Incursion (1,000) is the smallest standard size, and it’s enough to learn the game without a huge outlay.
Do I have to use one faction only?
In most game modes, yes. Allies are rare outside casual games, and you’ll normally build from a single Codex.
Can I use the same models with different detachments?
Usually yes. Detachment rules are rarely tied to a colour scheme, so you can swap them between games to change how your army plays.