Its a great, explosive card
: Destroy each nonland permanent with mana value X whose controller was dealt combat damage by this creature this turn
The flexibility to filter your hand while building a stronger board presence makes connive consistently valuable across different game states and formats
They also have a big old chunk of text that reads, Whenever another creature dies, or a creature card is put into a graveyard from anywhere other than the battlefield, or a creature card leaves your graveyard, Syr Konrad, the Grim deals 1 damage to each opponent. That means that your milling is killing, and you can just be chilling
The problem is that if you ever let a Creature come through unblocked, you have to give up the Coveted Jewel to your opponent and let them draw a bunch of cards
These cards also work well with our copy package