If an Attraction that is not normally an Attraction (probably because it's a copy of an Attraction) is destroyed, it will go to its owner's graveyard as normal, not their junkyard
Dion himself could easily helm a mono-white Knights deck, offering a very flickerable token generation and evasion, with a later game ability to pump the team and even blow up a permanent
If you just want cards that pack raw power, you might be more interested in the strongest Magic cards of 2021.
Its generally best to cast it on your turn, but the flexibility of playing it on your opponents turn is nice, and youll have plenty of options to discard since you see four new cards for 4 mana
But it's that opening-hand gamble that'll appeal to Tron players
Also try to exile their Bolas or threats