Undergrowth

Instant, G (1)
As an additional cost to cast Undergrowth, you may pay {2}{R}.

Prevent all combat damage that would be dealt this turn. If its additional cost was paid, Undergrowth doesn't affect combat damage that would be dealt by red creatures.¹
"It is the work of sorcery. Burn it!" -Taaveti of Kelsinko, Elvish Hunter
Illus. Pat Morrissey

Gatherer Card Rulings [Nov 2009]

• 10/4/2004: It means that red creatures still deal damage if you pay the additional cost.

Format Legality	Legal in Vintage, Legacy Banned in Extended, Standard, MTGO Classic
Versions (2)	Alliances #87 (Pat Morrissey) Alliances #88 (Pat Morrissey)
Printings (2/12)	Alliances (Common) → View All