The Mega Greninja ex MHR is no exception
Even ten retro formats would be inherently overwhelming for a new player, and those new players usually just ask the seasoned players what the most popular options are or just start playing one of the most modern formats on the website (If they dont already have some knowledge of retro Pokmon when they create their account, which many of them do)
Unlike 151 where if you rip an ETB and pull the main chase card, youre still in the negative this set has a chase card (Pikachu SIR) thats worth around $331, while the ETB costs about $99
Jim Davis recently went over some of the best reprints from the set over on the MTG Arena YouTube channel
UR Ultra Rare Scrap Warrior X EARTH Level 3 [ WarriorSynchroEffect ] ATK 1700 DEF 100 "Scrap Synchron" + 1+ non-Tuner monsters Monsters you control that mention "Junk Warrior", or are a Synchro Monster with "Warrior" in their original name, cannot have their activated effects negated (except "Scrap Warrior")
Some of these items are large, heavy and/or bulky (items such as Threaders, Benders, Panel Saws, Generators, etc)