A death trigger on a 7-drop is a hoop big enough to allow this beast to roam free, though as one of the best green tutors it can pull off some instant wins when it eventually dies
This card already copies itself thanks to the storm keyword , and so long as you've chained a few cantrips together beforehand, Elemental Eruption will give you an army of 4/4 flying Dragon Elementals that get bigger with every non-creature spell cast
Think of it like this: Dredge decks need to dump cards in the graveyard to trigger effects like Narcomoeba, so self-mill more or less equals drawing cards
Having one card that can be another Oblivion Ring to kill a planeswalker, another Sphere of Safety against creature decks, or another Rest in Peace against dredge seems perfect for the deck
Lifegain decks can leverage this quite well to create large swings
Dratini is classified as a 1-Star Shiny card in the Mega Shine set