by Qon

Broodmother is a spidertron that spawns baby spidertons that will follow their mother and attack for her. They get the same equipment (free, can't be taken out) as the mother and same ammo loadout (taken from her trunk).

a month ago
1.0 - 1.1
9 months ago
Latest Version:
1.1.1 (a month ago)
Factorio version:
1.0 - 1.1
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The Broodmother

is a spidertron that primarily attacks by spawning baby spidertrons that follow their mother and auto attack for it.

Spawning and arming the baby spiders

The babies get the same ammo loadout and equipment grid modules as their mother when spawned.

You need ammo in ammo slots and in trunk or personal laser defense equipment in the grid (or other modded active defense) or both to start spawning baby spiders.

Equipment is cloned on birth from the mother for free, but nothing in a baby spider's grid can be taken out.

For ammo that means type and count of each ammo slot will be the same as their mother, but it will be filled from her trunk on spawn if the mother's auto attack options are off.

This means you can set auto attack on while setting up correct types and counts in the ammo fields after filling up the trunk, without baby spiders spawning and taking full stacks before you are ready. And it means the broodmother wont auto attack when she can spawn baby spiders that can attack for her, so the ammo loadout isn't messed with. You can also drive the broodmother and have auto attack on and let broodlings only attack with personal laser equipment if you want that.


If a baby spider is too far from their mother or out of attacking options (no ammo and no attacking equipement) they explode immediately.

The broodmother uses some health to spawn a baby spider but also regenerates health over time.

Options and Balance


  • Scale of the broodmother and babies
  • Baby spidertron max health (default 100). Less might be a good option if you want them to die when attacked and have a new one spawned instead. More might work with slower spawning rate (other option)

Global runtime

  • Spawn baby spiders every nth tick. Default 20, which means 3/second since there's 60 ticksper second. Something like 120 (once every other second) might be worth testing too if you give them some extra health.
  • Max baby count. How many baby spiders each mother can have. More means that the babies will form a bigger circle and keep the same distance between eachotehr so it doesn't really correspond directly to balance alone.
  • Baby spacing multiplier: How much distance between baby spiders in the circle (actually: distance from mother = babies alive * spacing multiplier). Densly packed baby spiders will out DPS anything lowering it will make the circle smaller but kill things faster. If spacing is halved and count is doubled then circle will stay the same size but, and DPS will go up per area and in total.
  • Broodmother regen per second. Default 20.
  • HP cost to spawn a baby spider. Default 20.
  • Broodmother calls for help. Default True. If The broodmother is hurt then half the baby spiders will run back to their mother in order to get close enough to kill the attackers.

Balance can be adjusted with the options. But it's supposed to be an army of spidertrons, which means it's as strong as an army of spidertrons. It's almost unkillable for default 100% evolution natives even if you try to play recklessly if your weapons loadout is somewhat sane.

About the mod idea for the idea of a broodmother spider that spawns baby spiders
And Qon for the rest. Got some inspiration from Spidertron squad control. It's great but doesn't have formation options and setting up a squad with ammo and equipment was tedious. So this mod makes all that automatic after making the initial mother.

Optimization and future updates

Not yet. But you probably don't need that many Broodmothers anyways since they are a full army by "themselves". So it's nothing to worry about as long as you don't place too many of the Broodmothers at once.
So hopefully a future update should make it much more performant, but also add some cool new features so that the broodlings can be "detached" from the broodmother's control and stuff.


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