Spider Domain

Many creatures of the Underdark are drawn to the power of the spider and that of the master of spiders - the arachnomancer. The attractiveness of the arachnomancer class depends more upon the candidate's race, culture, and personal interest than it does upon class. However, all arachnomancers are spellcasters. Clerics with the Spider domain sometimes multiclass into arcane studies.

Most drow worship their spider goddess Lolth, and they tend to extend that reverence to most of spiderkind as well. Thus, arachnomancers usually enjoy high standing in drow society. Many other Underdark races, such as aranea or chitines, are spiderkind themselves, so they particularly enjoy the abilities that this domain grants them.

Speak with Spiders

When the cleric chooses this domain at 1st level, he or she can communicate with any spiderkind creature as a free action. Mindless creatures can communicate and understand only extremely simple concepts (one word at best), but they generally don't try to eat someone who communicates with them.

Poison Save Bonus

An arachnomancer adds her class level to all saves against poison.

Channel Divinity: Spiderform

Beginning at 2nd level, an arachnomancer may transform herself into a Spider, Giant Wolf Spider or Giant Spider three times per day.

This ability functions like polymorph, except that the indicated forms are the only ones available and the duration of the change is up to 10 minutes per arachnomancer level. Resuming normal form requires a standard action but does not provoke an attack of opportunity.

Webwalker

Beginning at 6th level, an arachnomancer can ignore webs (magical or nonmagical) as if affected by a freedom of movement spell. She can climb webs at his normal land speed without needing to make a Climb check and walk along webs, without needing to make a Balance check.

Wall of Webs

At 8th level, an arachnomancer gains the ability to create a wall-like barrier of webs once per day. Unlike the webs produced by the web spell, those in the wall of webs are resistant to fire and as tough as steel. A wall of webs functions like the wall of iron spell (caster level equals arachnomancer level), except that an arachnomancer can use her webwalking ability to move through the wall unhindered, and any other creature can use freedom of movement to do the same.

You can use this ability again after a long rest.

Spider Blast

Once per day, a 17th-level arachnomancer can produce a 50-foot-long, cone-shaped blast of extremely poisonous, normal-sized spiders. Every creature within the area of the blast takes 5d4 points of damage and must make 1d4 Constitution saves against poison (Spellcasting Ability DC; 1d6 points of Strength damage for both initial and secondary damage). Each creature is also allowed a Dexterity save at the same DC for partial effect: Success means the victim takes half damage and need make only one Constitution saving throw against poison (though the second saving throw normally required against a poison's secondary effect still applies). The spiders fade away at the end of the arachnomancer's turn.