Muri is the village elder where Dende comes from on Namek. When Freeza's forces captured and interrogated him, Muri managed to destroy all their scouters before they could kill him—a move that seriously set back Freeza's Dragon Ball collection efforts. He didn't survive the encounter, but the Dragon Balls brought him back.
After his resurrection, Muri got promoted to Grand Elder, which came with some pretty significant perks: he could restore the Dragon Balls' power whenever they were used up. Later, when the Namekians relocated to New Namek, he powered up Porunga (their version of Shenron) so the wish-granting dragon could revive multiple people at once instead of just one.
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