A good example is Obeka, Splitter of Secondss ability to add extra upkeep steps
While it looks tough to access at first, the card essentially gives you two land drops itself, one on entry and one when your Earthbent land is inevitably removed somehow, so it shouldnt be hard to get going
Bloated Contaminator trumps this card in terms of mana efficiency (spoilers), but Grafter provides card draw and ramp, something poison-based decks are severely lacking
This list includes Alpha , Beta , Unlimited , Collectors Edition (CE) , International Collectors Edition (IE) , Arabian Nights , Antiquities , Revised , Legends , The Dark , and Fallen Empires
Paired with proliferate cards from Phyrexia: All Will Be One , this brews a lethal deck
If you do, draw X cards, then put up to X land cards from your hand onto the battlefield tapped, where X is the sacrificed creatures power. Being able to throw away some of your cards for not just extra cards in your hand but also extra land in play is game-winning