Mercy

Picture this: you are an edgy plague lair and your username is Psycho to demonstrate this. No obsidian/red/white dragons exist because they are too damn popular and you are too damn poor.
One day, one appears! It's your favourite breed... it's also 1000 gems which is super expensive for a non-g1 - but it does have some art? Because you have no impulse control you buy gems with your meagre part-time paycheck and also gene it to perfection. You bedeck it in the finest outfit you've ever created. You buy the boneyard vista and you make her your profile picture for decades, hoping you leave an intimidating presence with your snarky and very cool forum comments. Your are so plague, the plaguiest plague that ever plagued, infact.

Time goes on, your life experiences change you and you leave your younger self behind..

You are no longer Psycho, the Plague fanatic, you become Heart, the colourful Nature lover.
You look at your edgy dragon and wince a little, what an a** back then I was, you think. You read your forum posts and try not to die of cringe but you also feel a touch of fondness for that person.

You decide to show mercy to the testament to your edgy younger self and preserve her in your lair forever.