From the Super Mario Wiki
Targeting Teds are a derived species of Torpedo Teds that first appear in New Super Mario Bros. U. Targeting Teds inhabit the water and look almost exactly like regular Torpedo Teds, though they are red instead of black. Much like Bull's-Eye Bills, Targeting Teds follow the player around until they explode. They are launched by Red Skull Boxes and are one of the few enemies that can destroy used Blocks.
Targeting Teds make their only appearance in the level The Mighty Cannonship, which is located at Soda Jungle. Bowser Jr. uses the Targeting Teds during the first fight, where the players have to redirect them at Bowser Jr. three times to defeat him.
Players using Boost Mode with the Wii U GamePad can tap a Targeting Ted to make it explode.
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