Spike Ball

Type	EnemyInvincible
Environment	Dungeon
AI Type	Spike Ball AI
Damage	32/64/96
Max Life	100/200/300
Defense	100
KB Resist	100%
Hurt	https://terraria.wiki.gg/wiki/File:NPC_Hit_1.wav
Killed	https://terraria.wiki.gg/wiki/File:NPC_Killed_1.wav

Not to be confused with Spiky Ball.

The Spike Ball is an invincible NPC found in the Dungeon which resembles a mace that swings around in a circle from a central pivot point (usually attached to a block), and deals damage to the player on contact. Separate Spike Balls can have differing chain lengths. Spike Balls spawn and despawn off-screen like any other enemy.

Slab walls

Faction flags
in this area:

Spike Balls spawn most often in areas of the Dungeon backed by slab walls. They can also spawn in other areas, but with a significantly reduced chance.

Notes

The Spike Ball's chain deals no damage.
If the block the Spike Ball is attached to is destroyed, it will continue to swing in midair.
(Old-gen console and 3DS versions) Since Spike Balls are considered enemies, many effects that usually apply to enemies apply to them as well. Note that none of these deals damage to Spike Balls.
- The Leaf Crystal that hovers above the player when wearing Chlorophyte armor fires at Spike Balls.
- Piranhas fired from the Piranha Gun can attach to Spike Balls.
- Pumpkins from The Horseman's Blade will follow Spike Balls.
- NPCs will attack Spike Balls.

Tips

Since it is usually dark in Dungeon, placing torches can help with keeping track of Spike Balls' path.

Trivia

The Spike Ball, along with the Blazing Wheel, True Eye of Cthulhu, and the flying Golem Head are the only four invincible enemies in Terraria.
The chain that swings the Spike Ball bounces up and down as it swings.
Spikes in the Dungeon inflict the Bleeding debuff, while the Spike Ball does not.