Every grade is saved to your collection automatically
To do this, you position Dialga-ex in the Active position and use the attack Metal Turbo with two energies to transfer energy to Arceus-ex
I mean, its annoying if you manage to forget both (as I have done on many occasion), but usually you can get away with just one

Fates Collide Theme Deck - "Battle Ruler" [Zygarde] $24.32 Fates Collide Three Pack Pin Blisters [Zygarde] Zygarde Collection Box Shiny Kalos Tin [Zygarde EX] XY - Fates Collide Sleeved Booster Pack [Zygarde] $52.97 Zygarde Complete Forme Pin Collection $150.00 Shining Legends: Shiny Zygarde GX Box Mega Zygarde ex Premium Collection $49.39 Carbink (49) #49Rare $0.53 Barbaracle #23Rare $0.40 Vullaby #57Common $0.11 Diglett #36Common $0.19 Carbink BREAK #51Rare BREAK $3.16 Servine #6Uncommon $0.30 Marowak #37Rare $0.45 Bronzor #60Common $0.12 Seel #15Common $0.15 Zygarde (53) #53Rare $0.45 Mega Zygarde ex - 046/080 #46Double Rare $0.29 Mega Zygarde ex - 047/088 #47Double Rare $0.56 Mega Zygarde ex - 071 #71Promo $0.51 Mega Zygarde ex - 097/080 #97Super Rare $5.09 Mega Zygarde ex - 104/088 #104Ultra Rare $5.51 Mega Zygarde ex - 113/080 #113Special Art Rare $31.08 Mega Zygarde ex - 117/080 #117Mega Ultra Rare $179.43 Mega Zygarde ex - 120/088 #120Special Illustration Rare $61.88 Mega Zygarde ex - 124/088 #124Mega Hyper Rare $139.15 Zygarde #XY152Promo $2.49

For many master set collectors, a high-grade 1st Edition Snorlax is the final and most expensive boss to beat
Thankfully there is a banned and restricted announcement this upcoming Monday, and not only is some kind of energy ban expected to happen, there could even be a substantial ban across the mechanic hitting multiple cards