(It's a black ability for those first time readers out there
[casthaven]Worldslayer[/casthaven], [casthaven]Decree of Annihilation[/casthaven], [casthaven]Worldfire[/casthaven], [casthaven]Jokulhops[/casthaven], etc theyre all just land-destruction cards gussied up to set people even further back
If you're playing a lot of small creatures, or maybe a commander like Adeline, Resplendent Cathar , then you'll find a lot of opportunities to draw cards - you might even be able to draw cards on opponents' turns with a bit of creativity
What I don't like, though, is having to care about everybody's graveyard
Use them well, and you can draw out your opponents spell and trap removal, chaining them to claim their effect