Argonaut Greatsword

This Greatsword seems ordinary at first glance, but upon further inspection, by someone with good intent, it seems to harbor overflowing potential. This sentient weapon glows blue, but only in the presence of a powerful threat.

You gain a +3 bonus to attack and damage rolls made with this magic weapon.

This weapon is immune to Detect Magic and Identify. The only way to tell it is magical is for a good character to make a DC 10 Investigation check.

This weapon Awakens after you commit a heroic act with it (DM discretion) and becomes Ascendant once you see the Tarrasque.

Abeyant:

This weapon has 8 charges and regenerates 2d4 charges per day at dawn.

Heroic Slash:

When you hit a creature that is one size larger than you with this weapon, you may expend a charge to cause the creature to take an extra 1d6 force damage or 2d6 if the creature's size is two sizes or more larger than you.

Awakened:

This weapon has 13 charges and regenerates 3d4+1 charges per day at dawn.

Personality:  When this weapon reaches the Awakened phase, the spirit of a long dead hero wakes up from its slumber to aid the person that saw potential in an ordinary greatsword. The sword has an Intelligence of 10, a Wisdom of 18, and a Charisma of 20 and has an alignment of Chaotic Good. The weapon also has darkvision and hearing out to 60ft. This weapon also insists that you look and act Heroic in combat or you cannot use Heroic Slash.

Heroic Slash:

When you hit a creature that is one size larger than you with this weapon, you may expend a charge to cause the creature to take an extra 2d6 force damage or 4d6 if the creature is two sizes or larger than you.

Argonaut Strike:

You may also expend 3 charges, upon hitting a creature that is two sizes or more larger than you with this weapon, to automatically crit.

Ascendant:

This weapon has 18 charges and regenerates 2d8+2 charges per day at dawn.

Heroic Slash:

When you hit a creature that is one size larger than you with this weapon, you may expend a charge to cause the creature to take an extra 3d8 force damage or 6d8 if the creature is two sizes or larger than you. 

Argonaut Strike:

You may also spend 3 charges, upon hitting a creature that is two sizes or more larger than you with this weapon, to automatically crit.

Reckless Abandon:

If you hit a creature that is two sizes or more larger than you, that also has legendary actions, you may expend up to 30 of your hitpoints and turn them into damage, if you expend all 30, the damage is 60. If this feature would bring you to 0 hit points, you automatically fail one death saving throw. This feature stuns you for 1d4-1 Rounds and automatically activates Argonaut Strike and Heroic Slash without using charges. After using this feature, you may not do so again for 1d6+4 days.

Tarrasque Hunter: 

This weapon ignores any resistances the Tarrasque has

This weapon cannot miss the Tarrasque and when you do at least 100 damage to it, you may delay it's regeneration for 6d100+50 years.

 

Proficiency with a Greatsword allows you to add your proficiency bonus to the attack roll for any attack you make with it.

Notes: Proficiency: Greatsword, An alternate name for this weapon could be (hero from your campaign) Greatsword, by a good character, Damage, Combat, Sentient, Heavy, Two-Handed, Graze