Another route to help boost your deck is using cards that protect from board destruction effects, like Heroic Intervention or Eldrazi Monument to make them indestructible
Throwing out an Exsanguinate after a mid to late game board clear to claw back some life buffer can be game winning, even if you have to go on to finish your opponents in other ways
Of course, this will see play in Dragon decks that just want to fill the skies, but its nothing exciting
Anytime Umbris, or another Nightmare or Horror creature enters the battlefield under your control, you get to exile cards from the top of their deck until they hit a land card
We also have a great article on 5-color commanders showcasing the true craziness that can be found in Commander
Its even possible to build cycling decks with five-color commanders like Jegantha, the Wellspring and include whatever cycling spells you want, as long as you have the mana to cast your payoffs