The problem is that it becomes a mana sink that you can only use on your own turn, rather than a way to invest leftover mana at the end of an opponent's or immediately after they drop a board wipe
If someone's playing a Tokens deck or otherwise has a big board state, that could easily be lethal for the whole board
While this wont grab land cards from your deck, if you combine it with some incidental card draw thanks to other colors, you can quickly end up with an unmatched number of Lands on board
The colors all bleed into each other and its all so punchy and kill-y
27 Tail Swipe Them's Fighting Cards It's not the most exciting card in the world, but Tail Swipe is a decent enough green removal spell, something the color is lacking
This one looks like sacrifice fodder, as it can come back from the graveyard again and again