They can be walked over, but will hurt Isaac for a full heart of damage when he touches them. Having Flight makes them harmless.
Various non-flying monsters are not invulnerable to spikes, and will take large amounts of damage from them.
Tips and Tricks
- Except for Mulligans and Hives, monsters will evade spikes. They can be pushed into them by shooting tears, though. This allows killing Hosts even if they are covered beneath their skull. Since monsters do not become invulnerable after taking damage (unlike Isaac), they will die very quickly once they touch spikes. This is even encouraged through the design of rooms containing Dople.
- Isaac can walk diagonally past two diagonally arranged spike tiles, which will result in no damage. It is even possible to walk vertically and horizontally between spikes without taking damage, but this is much more difficult to do than walking diagonally, and thus not recommended.
- Spikes have a different look in the womb, appearing to be crooked. Elsewhere, they are straight. This is entirely cosmetic and does not affect their behavior.
- Edmund has given contradicting answers on the slipping-through-spikes trick on whether or not it was intended.