Gishath is a powerful commander since it lets its controller play dinosaurs from the top of their library without paying their mana costs
Silverback Elder The options on Silverback Elder are always useful for the wise
Knowing three things allows you to act in the best capacity to win: what your deck can do, what your weakness is, and who is the biggest threat to you winning the game
Vishgraz, the Doomhive Vishgraz, the Doomhive makes a good number of other toxic creatures, and it can become quite the threat once youve distributed some poison counters
This includes all of the tutors that either fetch anything but lose a card (Vampiric Tutor, Imperial Seal) or grab one thing but puts it into your hand cheaply (Steelshaper's Gift, Buried Alive, Idyllic Tutor, Sylvan Scrying, etc.)