Iron ball

Spiked Balls also known as Iron Ball (鉄球), are variants that are described as heavy black / grey balls that have white or grey colored spikes around. These variants are first seen in 16-bit version of Sonic the Hedgehog, as spiked balls spins around at certain sections of Spring Yard Zone. Smaller spike balls appear swinging around at Labyrinth Zone, while bigger spike balls appear swinging back and forth at second act of Scrap Brain Zone. In Sonic the Hedgehog 3 and Sonic & Knuckles, there are specific large spike balls, that can have different methods such as swinging around in Marble Garden Zone dependent on the pole or rotating back and forth, even rotating to the player's neck at one point in Lava Reef Zone.

In later games since Sonic Adventure, spike balls become more occurring obstacles. These obstacles may be swinging around or dropping down and moving up while doing same method. In Sonic the Hedgehog (2006), Silver can grab these with his Telekinesis ability and utilize them to destroy enemies or other obstacles. Some spike balls may fall down to player's neck at Dusty Desert or Kingdom Valley. Games such as Sonic Unleashed and Sonic Generations, spike balls are set just on the player's way.