Arachna

Arachna is a single-level PWAD designed by Bjorn Hermans and Holger Nathrath and released in 1995. A version for Doom II was also released in 1995.

Secrets

 * 1) The southern switch on the exit structure can be accessed by pressing the wall in front of it. The switch itself raises the floor of the caged area to the south-west. It is possible to walk into this caged area (the floor can also be raised by pressing a switch inside it). There is a secret door in this caged area (marked with a misaligned texture) leading to a backpack and a soul sphere. (sector 281)
 * 2) Going north from the exit structure, go through either teleporter then go through either of the teleporters ahead to reach a star-shaped room. There are two switches on one of the walls – the wall opposite has a secret door (marked with a misaligned texture) leading to an invulnerability. Getting the invulnerability teleports you onto a cyberdemon. Both the sector before the teleporter with the invulnerability and the teleporter itself count as separate secrets. (sector 174)
 * 3) See #2. It is impossible to get credit for this secret, as you will be teleported away before reaching the sector. (sector 176)
 * 4) Several of the switches surrounding the blue key can be shot, opening various doors. The second one (starting from the north-west) opens up two secret areas, both of which count as separate secrets, near the start containing two lost souls, a shotgun guy, two imps (one on easy skill, a medikit, a megaarmor and a demon (not on easy skill). (sector 52)
 * 5) See #4. (sector 66)

Bugs
As it is impossible to receive credit for secret #3 (see above), the maximum possible secret percentage on this level is 80%.

Current records
The records for the map at the Doomed Speed Demos Archive are:

Things
This level contains the following numbers of things per skill level: