The cleanest source of all is simply lifelink any big lifelink creature or a Whip/Basilisk Collar effect turns combat into a lifegain trigger
By paying 2000 life points, you can send a Polymerization or Fusion spell from your deck to the graveyard, and have this guys effect become equivalent to that card
Now you can immediately use him over three turns to draw three cards, gain six life, and then move on, which makes him better than other card-drawing spells like Concentrate
If you prefer opening for singles value, standard boxes with strong chase cards (like Inferno X with Mega Charizard X ex) can also deliver but with more variance
During your Standby Phase: You can banish this card and 1 "Destiny HERO" monster from your GY
Ok Pokemon Trading Card Game Classic Collection (Pokemon Scarlet & Violet) Details All prices are the current market price