This backpack has a cable attaching it to a modified heavy crossbow covered in arcane symbols. If you pull the trigger on the crossbow as an action, instead of a bolt, a purple beam of crackling energy shoots from a glass tube mounted in the slot meant for a bolt. The beam darts forward to entangle a creature you can see within 20 feet of you. The target must succeed on a DC 15 Dexterity saving throw or become restrained, wrapped in the energies. It does not damage the person or creature held.
After 3 consecutive rounds of use, the backpack and crossbow began to overheat. In the 4th round, the user takes 1d6 points of heat damage from the backpack is still worn and 1d4 from the crossbow if still held. Damage doubles each round thereafter. Additionally, in the 4th consecutive round of use, there is 10% chance the backpack explodes, causing 6d6 of explosive damage. Each consecutive round of use thereafter the chance of explosion increased by 10%.
The item will take one round of non-use to cool off after 3 consecutive rounds of use, plus one additional round for each consecutive round thereafter.
The item will come with 1d10 rounds of energy left. Once the charges are depleted the large purple diamond inside will disintegrate. It will need to replaced with a purple diamond of a minimum 10,000 GP in value, and a Glyph of Warding (Explosive runes) cast as a 7th level spell.
Proficiency with a Heavy Crossbow allows you to add your proficiency bonus to the attack roll for any attack you make with it.
This weapon has the following mastery property. To use this property, you must have a feature that lets you use it.
Push. If you hit a creature with this weapon, you can push the creature up to 10 feet straight away from yourself if it is Large or smaller.
Notes: Restrained, Control, Ammunition, Heavy, Loading, Range, Two-Handed, Push