Levels with a lava/volcano theme

From Sonic Retro

Sonic Retro emblem.svg Level themes
Lava/volcano theme
Lava Reef Zone from Sonic & Knuckles is an example of the lava/volcano theme.

The lava/volcano theme represents gameplay where the player must avoid bubbling lava, difficult traps, and fire-based badniks. This theme first appeared in Marble Zone in Sonic the Hedgehog.

Due to the abundance of lava traps, these levels are often higher in difficulty and may appear later in the game. Notable exceptions to this are Sonic the Hedgehog’s second level, Marble Zone, and Sonic the Hedgehog 2 (8-bit)’s first level, Underground Zone.

Levels with a lava/volcano theme