The main catch is the mana base: five colors punishes shaky fixing, so having the best dual lands (or at least strong substitutes like shocks/triomes) makes the deck feel much smoother
Most of its early- and mid-game cards like Paldean Wooper, Arbok, and Grifaiai poison your opponent's active Pokemon, with Grifaiai in particular being able to do so from the bench, while Paldean Clodsire ex does double damage if the opponent's active Pokmon is poisoned
This may also leave the target with paralysis

Mime #27Rare $6.55 Pidgeotto #28Rare $5.14 Pinsir #29Rare $4.49 Snorlax #30Rare $30.08 Venomoth #31Rare $4.78 Victreebel #32Rare $5.02 Arcanine #33Uncommon $1.92 Butterfree #34Uncommon $1.54 Charmeleon #35Uncommon $2.26 Dewgong #36Uncommon $1.74 Dodrio #37Uncommon $2.45 Dratini #38Uncommon $1.26 Exeggutor #39Uncommon $1.39 Farfetch'd #40Uncommon $0.65 Fearow #41Uncommon $1.41 Growlithe #42Uncommon $1.83 Haunter #43Uncommon $1.64 Ivysaur #44Uncommon $8.09 Jynx #45Uncommon $1.10 Kadabra #46Uncommon $2.38 Kakuna #47Uncommon $0.93 Lickitung #48Uncommon $1.76 Machoke #49Uncommon $0.82 Magikarp #50Uncommon $2.40 Magmar #51Uncommon $1.22 Marowak #52Uncommon $2.00 Nidorina #53Uncommon $1.22 Nidorino #54Uncommon $1.41 Parasect #55Uncommon $1.24 Persian #56Uncommon $2.62 Poliwhirl #57Uncommon $1.40 Raticate #58Uncommon $1.31 Rhydon #59Uncommon $2.04 Seaking #60Uncommon $1.39 Charizard #4Holo Rare $466.74 Blastoise #2Holo Rare $147.25 Venusaur #18Holo Rare $99.41 Mewtwo #10Holo Rare $62.32 Raichu #16Holo Rare $55.92 Alakazam #1Holo Rare $55.62 Gyarados #7Holo Rare $42.70 Nidoking #11Holo Rare $42.69 Zapdos #20Holo Rare $39.56 Pidgeot #14Holo Rare $38.31

Sac clogs up the ground from blocking, while grinding down your life total with cat/oven
Using pawn shops should be a last-resort option, as you may not get the full value for your cards