Edison format ruling
Informer Spider

Card effect (current official text)When this card is sent from the field to the Graveyard by a card effect, take control of 1 Defense Position monster your opponent controls.
Rulings
- This effect targets 1 Defense Position monster. This effect activates even if "Informer Spider" is destroyed during the Damage Step.
- The effect of "Informer Spider" does not activate if it is sent to the GY as a cost to activate a card or effect.
- If "Informer Spider" is sent to the GY when all your Monster Card Zones are full, the effect will activate and you will target a monster. The targeted monster will be destroyed when the effect resolves because you cannot take control of it.
- You gain control of the targeted monster for as long as it is on the field.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Edison forum — sourced change requests get reviewed.