That’s the case with the art description rk post was sent for the spell that would eventually become Flame Jab:
Color: Red spell
Location: Ashen remains of a burned forest
Action: show a stylish lick of flame bursting from one of the still smoldering trees in the land card you painted for us. an ember has magically been exploited to burst forth into flame and do damage!
Focus: the flame spout
Mood: Here comes a third-degree burn... Haiii--(YAH!)
In this case, the land card in question is rk post’s Shadowmoor Swamp. Why a Swamp, you might wonder? In Shadowmoor, the cinders—the guttered husks of Lorwyn’s flamekin—are strongly aligned with both black and red mana. That means a black-producing land makes perfect sense as the site for a red spell... especially one that you can discard that same land to play!