While there are some diminishing returns with Naban, Dean of Iteration and Snapcaster Mage, since you need mana to cast the spell you flash back from the graveyard, the potential to play a Snapcaster Mage on Turn 4 and flash back a Thoughtseize to take your opponent's best card while also getting to Serum Visions or Thought Scour is pretty appealing
In it, I made the following card: In design, the card was called "Plague Bolt," as its design was trying to take what Plague Rats did and apply it to a direct-damage spell
This is one of those cards which is made worse by looking at the flavour text, which reads: They call it stitchers anaesthesia, a spell to deaden the senses while the mad doctors begin their grisly work. That means that this person is not only alive, but about to be butchered and probably sewn onto a bunch of other people to make a Skaab Goliath or something
Here are cards that are easy recommendations in the 99 of your Commander deck
Red and black have the most consistent ones, in my opinion