Cannot be Normal Summoned or Set. Must be Special Summoned (from your hand) by Tributing 3 monsters, including at least 1 "Destiny HERO" monster, and cannot be Special Summoned by other ways. If you still control this face-up card during your opponent's next Standby Phase after you Special Summoned it: Halve your opponent's Life Points.
If this card is Normal Summoned: It is treated as a "Destiny HERO" monster while it is on the field. You can only use each of these effects of "D3" once per turn.● You can discard up to 2 cards; Special Summon the same number of "D3" from your hand, Deck, and/or Graveyard, also you cannot Normal or Special Summon monsters for the rest of this turn, except "Destiny HERO" monsters.● If this card is destroyed by battle or card effect: You can send 1 "Destiny HERO" monster from your Deck to the Graveyard.
If you have 3 or more "Destiny HERO" monsters in your Graveyard: You can discard this card, then target 1 "Destiny HERO" monster in your Graveyard; Special Summon it to your opponent's field in Defense Position. Negate any Spell Cards or effects you activate, and if you do, destroy that card. During your Standby Phase: You can banish this card and 1 "Destiny HERO" monster from your Graveyard; each player chooses 1 Normal Spell Card from their Deck and places it on top of their Deck.
If this card is Normal or Special Summoned: You can send 1 "HERO" monster from your Deck to the Graveyard. You can only use this effect of "Vision HERO Vyon" once per turn. Once per turn: You can banish 1 "HERO" monster from your Graveyard; add 1 "Polymerization" from your Deck to your hand.
1 "Destiny HERO" monster + 1 DARK Effect MonsterDuring either player's turn: You can discard 1 card; send 1 "Destiny HERO" monster from your hand or Deck to the Graveyard, and if you do, all "Destiny HERO" monsters you currently control gain 200 ATK for each "Destiny HERO" monster currently in your Graveyard, until the end of this turn. You can only use this effect of "Destiny HERO - Dangerous" once per turn.
Honestly the <name> Guy names sound pretty bland to me. Sometimes they're both kinda meh (Blademaster vs Dagger Guy), but a lot of the time it's an improvement. I like Dangerous more than Destructive Guy, and some, like Dogma or Dasher are clear improvements.
If you want to run pure destiny heroes then yes since the best cards are only 1 copy per deck. You could mix this with some dark hex and slash dragon and make it a decent fusion deck with some backrow.
Even if you buy 3 of the structure deck, it's not a meta defining deck.