Trace of Abundance is a common Enchantment — Aura card from Secret Lair Drop (SLD), collector number 1849. Current market price: $1.09, TCGplayer market prices via Scryfall.
Enchant land Enchanted land has shroud. (It can't be the target of spells or abilities.) Whenever enchanted land is tapped for mana, its controller adds an additional one mana of any color.