Whip of Spiders

From your sleeves, pockets or other obscured places emerge hundreds of tiny spiders. Gathering at your hand, they link together to form a long whip. You are considered proficient with this weapon, and it has the finesse and reach special qualities. This weapon cannot be unwillingly disarmed, and if you are targeted by a spell which targets an area of effect, the whip of spiders is considered to have evasion so long as it is in your hand.

As an action, you may make an attack with this whip, dealing 4d4 piercing damage as the spiders swarm over the target. If the whip is reduced to less than half of its maximum hit points (see below) reduce the damage dice by half, rounded down.

As a bonus action, you may drop the whip and have it turn into a swarm of spiders in your space. The swarm has 22 hit points and and AC of 12, and is an ally to you and your companions. In combat, it shares your initiative count and uses your proficiency bonus. It obeys your verbal commands (no action required by you). If you don’t issue any, it takes the Dodge action and uses its move to follow you, sharing your space if possible. If the swarm is within your space on your turn, you may use a bonus action to command it to take its whip shape and return to your hand.

At Higher Levels: When you cast this spell using a spell slot of 3rd level or higher, the damage of the whip increases by 1d4, and the swarm adds 10 to its maximum hit points, and 1 to its Armor class.