Kyle (5e Equipment)
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Weapon (Greataxe), Legendary (Requires attunement by Fighter or Barbarian)
This axe is made of dark wood, with black iron for the blades. Where the blades meet, there are three claw marks, bright green in color, on each side. The marks are nearly identical on each side. This weapon's creation date and origin are unknown, as the spirit inside either doesn't remember or doesn't care enough to answer any questions regarding either path of query.
Upon attunement, this weapon loses the Heavy property and gains the Thrown (20/40) property. If you throw this item, it will return to your hand at the start of your next turn, regardless of if someone picked it up.
Whenever Kyle reduces an enemy to 0 hit points or kills it, Kyle gains Monster Energy points equivalent to the monster's CR-10, divided by 2 (an Ancient Red Dragon would give 24-10=14, 14/2 = 7 Monster Energy points). Upon finding this weapon Kyle has 1d6-1 points stored in it. Kyle can store a maximum of 20 points at a time
Monster Energy Cleave Upon attacking a monster with this weapon, you may choose to spend 1 point within this weapon. If you do so, all monsters within a 15 foot cone must make a DC 17 Dexterity save, taking 1d6 acid + 1d6 lightning damage.
Monster Energy Strike
Upon throwing this weapon and hitting the enemy, you may choose to spend 2 points and activate this ability. A bolt of green lightning comes down from the sky, dealing 3d10 acid and 3d10 lightning damage to the target, in addition to the greataxe's standard damage.
Monster Energy Drive You may spend you movement, action, and bonus action, as well as expend all points from this weapon, to slam the weapon into the ground, creating a fissure crackling with green electricity in front of you. This fissure travels 5x the amount of charges spent in feet, has a width of 5 feet, and forces all monsters in it's path to make a DC 20 Dexterity save. A failure deals Xd12 acid and Xd12 Lightning damage, where X is the number of points spent on this attack. Any monster killed with this attack adds at least one point to the amount stored within Kyle, more if the monster is worth more points.