The card only gave the Harpie it was equipped to 300 extra attack and defense points, so there was no reason to keep it around after season one when the power level of the game increased
If you lose the monarch ability, attacking with Aragorn helps you recover it
The card features a visually stunning illustration depicting Mega Rayquaza exs body surrounded by a rash of colors as it unleashes an attack
Casting Aetherize at four converted mana cost is very overkill, but with Cyclonic Rift, you can just pay the normal one-generic, one-blue cost to deal with the problem instead
If theres a second copy of that monster in your opponents Graveyard, you can use Called by the Grave to banish that duplicate copy when your opponent activates the effect of their on-field monster
Check out this Twitter thread from Rainville showing how the Heart of Fire came to life