Enchantment Rite of the Raging Storm Creatures named Lightning Rager can't attack you or planeswalkers you control
Trainer gallery cards share a similar rarity to some alternate art cards and ultra rares, meaning you can expect to find one once every 10 to 20 packs
Prices change with demand, new set releases, hype cycles, supply, and fresh graded sales
Except these memories can attack and block
Hau #144 Pokemon Guardians Rising Keep track of your collection value over time
The article also indicates that nonfoil Shattered Glass is about as common as foil Generation 1 cards, so we get a rough breakdown of 75% nonfoil G1 (6 of 8 packs), 12.5% nonfoil Shattered Glass (1 in 8), 12% foil G1 (again, about 1 in 8) and finally foil Shattered Glass, which will be the 1 in 151 or so that we got from Hidetsugu, less than 1% chance