Need. . .more. . .pixie. . .dust. Eoin Colfer's Artemis Fowl series about a young, nefarious Irish mastermind and his adventures with fairies has always been staunchly uncute. The elves and centaurs Artemis runs with (and often runs a-fowl of) are technology-toting, gizmo-obsessed bad-asses. But in this fourth edition, Artemis Fowl: The Opal Deception Colfer is practically channeling Tom Clancy. Fowl and wary elf Holly Short reteam to keep a ''murdering pixie genius'' named Opal Koboi from pitting humans against fairies. The characters especially sarcastic Artemis, now 14 are still a blast, but Colfer seems too dazzled by all the gadgetry and explosives jammed into this tale.