Diabrand, The Sword of Summer

Martial Melee Weapon (Longsword), Legendary (Vestige of Divergence), Requires Attunement

“This Sword is a symbol of the pact between the Estival Queen, and her mortal knight. Its very presence commands respect from anyone with fey heritage, or knowledge of its court hierarchy. Anyone who stands in the way of the Summer Knight will quickly see their end by this blade.

Diabrand itself is crafted from magical gold, its edge enchanted with the blazing heat of the summer sun, and decorated with the verdant growth of the bright season. A small star sits at the pommel of the blade, channeling the heat and light of the day star.”

Dormant

You gain a +1 to Attack and Damage rolls with this magical weapon. 

When making an attack with this weapon you may cast the Green Flame Blade cantrip. When casting Green Flame Blade in this way, if you do not have the spellcasting ability, you may use Strength or Dexterity modifier to determine the amount of Fire damage done. 

Awakened

“When Diabrand awakens, the golden, vine-like guard of the blade begins to flourish. Golden leaves begin to unfurl from the guard, as the star on its pommel begins to blaze.”

Your Attack and Damage rolls with this magical weapon increases to +2

Enemies who end their turns within 5 ft. of you must make a DC18 Dexterity saving throw or take Fire damage equal to your Charisma modifier

Exalted

“Once The Sword of Summer reaches its Exalted state, its wielder is granted the full measure of the Summer Queen’s power. The day star burns brightly, its light and heat reaching its zenith unleashing an aura of summer radiance in the immediate area.”

Once per Long Rest, when you hit a creature with an attack, you may empower your blade to perform a Green Flame Smite. The creature you hit takes the normal weapon damage plus an additional 8d8 Fire damage. All enemy creatures within 15ft. of the target also take 8d8 Fire damage, as small green explosions fill the air around them. 

You and allies within 30 ft. gain resistance to Fire damage.