Thorn Spring

The Thorn Spring is a reoccurring gimmick that appears in the Sonic the Hedgehog series. It is a hazardous variant of the Spring which has spikes equipped on the bottom.

Description
The Thorn Spring is a floating object with a standard modern Spring on top and a metallic cup on the bottom which surface is covered in spikes. In gameplay, the Thorn Spring flips itself upside down for a short while in fixed intervals, making either its Spring or spikes point upward. The player can either touch them normally or target them with a Homing Attack.

When touching the Thorn Spike while the Spring-side is up, it works like a regular Spring, launching the player through midair to another location. If the spike-side is up though, the player will take damage upon touching it. Using this gimmick properly is thus based on timing.

Sonic Unleashed
The Thorn Springs first appeared in the in Xbox 360/PlayStation 3 version of Sonic Unleashed. In this game, they are only found in the daytime Action Stages. They are also not very common, only appearing in Jungle Joyride Act 1 and a few non-obligatory Acts.

Sonic Colors
In Sonic Colors, the Thorn Spring only appear in the Wii version of the game.