In Search of the Ruby Rainbow - The Tales of the Magic Piano, #1

Have the time-travellers' final days arrived, or will they actually get home? Despite the many fears of their travels, Nedebiah Jericho, The Time Warp Keeper of Karman and his brood of time-travelling companions, journey the length and breadth of the universe as they battle the wicked Grand Wizard of Balthazar. With tragedy and triumph revealed in every dramatic chapter, Nedebiah and his earthly friends, Marius, Nicolas, Henry, Elise and Uncle Olaf, set forth into the great unknown in search of the Ruby Rainbow, a cosmic pathway in time miraculously constructed by the fearsome, alien imperialists, the Shakrel.
Time is not on their side as they travel through the four portals of time from distant fantasy worlds of frost-breathing paladins and knights to the beautiful realities of the South African wilderness to the majestic, subaquatic fantasy world of King Triton and his merfolk. All the while, the Grand Wizard seeks the wondrous 'pure essence of time', a powerful druid substance which enables the time-travellers to leap between dimensions.
Aided by his brutish bevy of warlocks, wizards and witches, they make for a fearsome enemy. Yet good fortune shines upon the time-travellers who remain protected by the ethereal spirit of the Shaman of Sashebah, Chancellor Bahlizhor of the Soothsayers Guild and the beautiful Queen Shoshana, a wonderful monarch whose mothering spirit of love and devotion watch over them. Finally, a light shines on the horizon.
Is it the Ruby Rainbow or is it something more sinister?