Tengu format ruling
Dark Valkyria
Card effect (current official text)This card is treated as a Normal Monster while face-up on the field or in the Graveyard. While this card is a Normal Monster on the field, you can Normal Summon it to have it become an Effect Monster with this effect.
● Once, while this card is face-up on the field: You can place 1 Spell Counter on it. This card gains 300 ATK for each Spell Counter on it. You can remove 1 Spell Counter from this card, then target 1 monster on the field; destroy that target.
Rulings
- While Dark Valkyria is an Effect Monster, you can place Spell Counters onto it with other card effects, like Pitch-Black Power Stone and Apprentice Magician.
- If Dark Valkyria is treated as an Effect Monster due to the effect of "Superalloy Beast Raptinus" and has a Spell Counter when Superalloy Beast Raptinus is removed from the field, the Spell Counter is removed because Dark Valkyria is changed to a Normal Monster. If Dark Valkyria becomes an Effect Monster again afterwards, its effect can be used once more.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Tengu forum — sourced change requests get reviewed.