If you control no creatures other than Joo Dee and no artifacts as the ability resolves, you'll need to sacrifice either Joo Dee or the token copy
What type of combo is Sacrifice + Shallow Grave + Scholar of the Ages
Its a great way to punish greedy turns and protect your own combos without relying on hard counters
I was taken through a standard tutorial which taught me the very basics of the game, from how to assign an active Pokmon to evolution, which turned out to be short and sweet - to my great delight and surprise

Team Aqua's Kyogre EX RR :1ED [CP1 006/034](Concept Pack "Magma Team VS Aqua Team Double Crisis") Retail US$ Team Magma's Groudon EX RR :1ED [CP1 015/034](Concept Pack "Magma Team VS Aqua Team Double Crisis") Retail US$ Sylveon EX RR :1ED [CP3 026/032](Concept Pack "Pokekyun Collection") Error Version Retail US$ Flareon EX RR :1ED [CP3 007/032](Concept Pack "Pokekyun Collection") Retail US$ Pikachu RR :1ED [CP3 010/032](Concept Pack "Pokekyun Collection") Retail US$ Charizard EX SR :1ED [XY2 081/080](Expansion Pack "Wild Blaze") Retail US$ Charizard EX SR :1ED [CP6 090/087](Concept Pack "Pokemon Card Game Expansion Pack 20th Anniversary") Retail US$ Gengar EX SR :1ED [XY4 090/088](Expansion Pack "Phantom Gate") Retail US$ M Charizard EX SR :1ED [CP6 091/087](Concept Pack "Pokemon Card Game Expansion Pack 20th Anniversary") Retail US$ Umbreon EX SR :1ED [XY10 082/078](Expansion Pack "Awakening Psychic King") Retail US$ The rustle of a booster pack, the tantalizing glimpse of a foil edge, the breathless anticipation of what lies withinthese are the sensations that bind generations in the shared passion for collecting Pokmon cards

So for me, this combo belongs in a Bracket 4 deck