All Spiders only have four legs instead of eight.

In the Afterbirth expansion, they can be spawned by Black Globin's Body.

In Rebirth, they can be spawned by numerous enemies such as Nests and larger versions of Baby Long Legs.

In Rebirth, they will spawn from blowing up vases.

In Rebirth, Spiders can be also spawned by The Adversary.

Besides naturally spawning in some rooms, Spiders are also spawned when fighting Sacks, Widow, The Husk, The Wretched, Super Sloth (2 at once) and when destroying the smallest part of the Teratoma (also 2 at once).

A pair of Spiders can be spawned after killing the Big Spider.

When blowing up the Shopkeeper, 2 Spiders has a chance to be spawned.

Outside of combat, 2 Spiders can occasionally spawn from a Red Chest and will always be spawned if Isaac blew up a Devil Beggar.

They have an ability to go through small spaces, such as when 2 rocks are on a diagonal line, the spider can go through the small point created by the corners of the rocks. Thus, it is extremely difficult to kill these particular spiders without taking damage or the use of bombs. Some rooms may spawn with the spiders around a corner formed by rocks, where the spider will stay until Isaac goes directly in front of it. As such, it's best to stay as far from them as possible. Spiders are incredibly speedy when dashing, making quick thinking and dodging essential to fighting these enemies.ĭue to their small size, they can even fit between the corners of some rocks. However, if they have a direct line of sight on Isaac, and are close enough, they will move towards him. Spiders move very quickly and will go in all directions randomly, making them unpredictable.

Binding of isaac spider mod