Its relatively easy to trigger and can allow for some nasty interactions
The deck can also try out beaters like It That Betrays or Inkwell Leviathan
Here are a handful of those damage doublers, be mindful of any that offer increases to opponent's sources of damage as well: Angrath's Marauders, Twinflame Tyrant, Fiery Emancipation, Fiendish Duo, City on Fire, and Fated Firepower
The ability that defines Duelist of the Mind's power works in all zones, not just the battlefield
While the Worldsire doesn't have trample or any other form of evasion, it should be large enough that you can kill anything that crosses its path, and the land ability should be what you're using this for, with things like Valakut, the Molten Pinnacle or Field of the Dead