They can double-chump to stave off your menace creature, sure, but that triggers enrage and throws around even more damage or removal
You can effectively undo your opponents and shift the power to your side of the board, and thats good in every single match-up (including Yorion, where the 4/5 is often very effective at holding you back)
Because your deck is 100% certified green energy, your opponent cant hope to defeat you with combat damage and instead must turn to mill, direct damage, enchantment removal, or other fiendish tricks
They are now a defining part of the Legacy and Vintage formats, in particular for their ability to be found by the various "fetchlands" (for example, Flooded Strand) released many years later
Whether you are an experienced player or a beginner, remember that this experience involves more than just playing a game it entails channeling imagination and strategic thoughtfulness