More like Crystal Keepers

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Five KingdomsSeries
series5 books2014
About quests.
“After Cole sees his friends whisked away to some mysterious place underneath the haunted house, he dives in after them—and ends up in The Outskirts.”
from the catalogue
Start with Sky Raiders →
Tolkien's legendariumUniverse
universe163 books1923
Fantasy, set in secondary world.
“Before the seas were bent and the mountains raised, there was Music — and from that Music came Arda, and in the west of Middle-earth the long defeat and stubborn hope of those who dwell there.”
from the catalogue
Start with The Fellowship of the Ring →
includes The Hobbit, The Lord of the Rings, The History of Middle Earth, The Fall of Gondolin, The History of the Lord of the Rings
NarniaUniverse
universe38 books1950
Fantasy and portal fantasy, set in secondary world.
“Once there is a wardrobe at the back of a spare room, and behind the fur coats the wood gives way to snow, and a lamp-post burns alone among the trees.”
from the catalogue
Start with The Lion, the Witch and the Wardrobe →
includes Narnia, Narnia Solo Adventures
BeyondersSeries
series4 books2011
Epic fantasy, about quests and prophecy.
“Jason Walker has often wished his life could be a bit less predictable--until a routine day at the zoo ends with Jason suddenly transporting from the hippo tank to a place unlike anything he's ever seen.”
from the catalogue
Start with A World Without Heroes →
AlmuricSeries
series1 book1964
About survival.
Start with Almuric →
SpellsingerSeries
series9 books1983
About quests and music.
“Alan Dean Foster's Spellsinger series follows Jon-Tom, a UCLA law student pulled into a fantasy world by the wizard Clothahump, where he discovers he can cast spells by singing along with his guitar.”
from the catalogue
Start with Spellsinger →