For one Blue to function as a discard effect or a Lightning Bolt to each player is pretty good
Dark Depths combos use the graveyard well, as do ones leveraging Fastbond (in the few formats it's legal in)
The most obvious way to use Senu to great effect is by pitching him to your Solitude when evoking it from your hand
Payoffs Usually, when I build token decks, I like to smash the opposition
While in the Graveyard, banish him to Special Summon a Sacred Beast from your Graveyard
Krrik, Son of Yawgmoth K'rrik, Son of Yawgmoth is one of the strongest mono-black commanders, one of the best mono-color commanders overall, and all-in-all one of the best lifegain commanders