Ylego's Remembrance, Oord's Claymore

This blade is a Weaveshredder, one created by the Spellbreaking Gith. This unique weapon bears the properties of both a Greatsword and Polearm, allowing an Attacker to roll 2d6 on a hit and attack at a range of 10 feet. Once per long rest, you can make an opportunity attack against an enemy casting a spell (as the Mage Slayer feat allows) and create tears in the weave itself. As part of this attack, you may replicate the effects of Counterspell cast at 5th level.

The wielder also has a +3 bonus to attack and damage rolls. The wielder may also increase their AC by +1 for each piece of the Tivaerian Armour of Kings they have equipped. With the full set, the armour also takes on the effects of Armor of Invulnerability. 

Finally, the wielder of this sword can declare their strikes to be non-lethal, but still incapacitate enemies (unconscious), and using their Investment of Will, can grant use and Attunement of this weapon to a non-fate-touched Tivaerian citizen for 1 day.