ibz10g's original description: "This is a base hack. I've modified the graphics of Super Mario World in such a manner that I feel captures the game's original feeling, yet at the same time gives you a sense of renewal. You may use this as a base hack, and credit will not be required. Please feel free to pick and choose from these graphics. I've got a little correction for anyone who reads this."
With this said, have fun and give credits to the original author.