Edison format ruling
Gradius' Option

Card text as printed in this era© Can't be Normal Summoned/Set.
© Must first be Special Summoned (from your hand) by targeting 1 "Gradius" you control.
① This card's ATK/DEF always become equal to that target's.
② If that target leaves the field, destroy this card.
Rulings
- As long as this card was initially Special Summoned by its own procedure (and the summon wasn't negated), you can Summon it from the GY with card effects.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Edison forum — sourced change requests get reviewed.