Spiderbane

Weapon (longbow), legendary (requires attunement by a ranger)

Prerequisite(s): You must have swamp or underground as a favored terrain type to attune to this bow.

This +3 longbow is made of fragrant gray yew. The bow is distinguished by a spiderweb pattern and the outer facing contains a decorative piece of amber with a large venomous spider trapped inside. The bowstring is composed of unbreakable spider silk enchanted to be as reliable as any normal bowstring.

Radiates: Conjuration and transmutation.

Powers:

• You gain the giant wolf spider’s web walk trait and may cast spider climb (self only) at will.
• When you hit with an attack on any insect-like creature or creature with a climb or a burrow speed, you do double damage on a regular hit and triple damage on a critical hit.
• Your arrows loosed from this bow deal an extra 1d8 poison damage.
• You may cast web on one arrow. Hit or miss, the spell goes off where the arrow strikes. You may use this power a number of times per day equal to your proficiency bonus, but must complete a short or long rest between uses.

Special: As a reaction to casting your web, you may summon a swarm of insects (spiders only) originating on that arrow. These spiders have the same statistics as a (variant insect) swarm of spiders, but their bites also do the poison damage of a swarm of poisonous snakes.

The swarm remains and attacks anyone in the web for 1 minute, until you lose concentration, fall unconscious or die, or you choose to dismiss the swarm as a bonus action. If the swarm has no creature left to attack in the web or the web is compromised (such as set on fire), the swarm pursues any creatures it was attacking in the web.

If no such creatures remain, it moves to attack remaining hostile creatures. The swarm will not attack you or your allies. You have no other control over it or way to communicate.