A "Gem Mint" 10 graded by trusted experts like PSA, BGS, or CGC can be worth 100x more than a "Near Mint" 7
There's no easy way to load your opponent up on one shot with Toxic, as they will both take regular damage as well as get the set number of counters from the Toxic ability
Once you flip Fable to Reflection of Kiki-Jiki, you get another Goblin Shaman, this one lets you make copies of nonlengedary creatures you control, giving them haste but forcing you to sacrifice them at the next end step
Its collectible value is boosted further by its rarity and limited pull rate, making it a centerpiece for many Japanese Pokmon card collections
Secondly, it gives a power boost, so you can kill out of nowhere faster or with a 9-power dork that doesn't have infect at all