"Pay 1 life, Sacrifice this land: Search your library for a [basic land type(s)] card, put it onto the battlefield, then shuffle." A fetch land in MTG is a land that lets you sacrifice it to search your library for a land with the specified land type(s) and put that land onto the battlefield
Sheoldred can also allow its controller to draw their entire deck, without losing due to self-mill, when combined with Lichs Mastery
Once per turn, you can flash back an instant or sorcery, effectively doubling up on your most critical combo pieces
Experience reprints from Magic's history in the art and story of Final Fantasy Commander Decks
Ive been very critical of Azorius Control decks early into the format, as the lack of other win conditions besides Teferi, Hero of Dominaria is concerning
The Commander Rules Committee has stated that this is because it is very hard to kill more than a single player with poison, especially because your opponents likely are not piling on with their own infect creatures