Goat format ruling
Magic Drain

Card effect (current official text)When your opponent activates a Spell Card: They can discard 1 Spell Card to negate this card's effect, otherwise negate the activation of their Spell Card, and if you do, destroy it.
Rulings
- Q: Player A: Activates a Spell Card. Player B: Chains with "Magic Drain." If Player A has a Spell Card in his/her hand must the Spell Card be discarded or is this optional? A: Player B can choose not to discard a Spell Card from their hand and can allow their first Spell Card to be negated.
Rulings data courtesy of Format Library — formatlibrary.com. Spotted an inaccuracy? Flag it in the Goat forum — sourced change requests get reviewed.