keen jolt
I had encountered this seed playing the checkered deck on red stake.
The mime shows up in the first shop inside the joker pack
The baron and blueprint can be found in ante 3 in the shop
Burnt joker also shows up in the run early to help level up your hands.
Anti matter is available around ante 11 if you bought the blank voucher. It's very beneficial as brainstorm can be found shortly after the antimatter voucher.
primal kernel