Lava

Lava is a hazard that appears in many Mario games. It mainly serves has a harzard where if Mario touches one, he instanly dies though this effect is different in games like Super Mario 64 and Super Mario Sunshine. Lava is usually home to Podoboos and is Bowser's main harzard he has in his castles.

Super Mario Bros. series
Lava appears as a harzard in Super Mario Bros., Super Mario Bros. 2, and Super Mario Bros. 3. Lava mainly appears in Castle levels where if Mario falls into it, he instanly dies. In Super Mario Bros, this is a classic way of finishing off Bowser at the end of levels. Podooboos also tend to jump out of lava in these games.

Super Mario World
Lava appears in many levels in this game where it's purpose is the same as in the Super Mario Bros. games. The first castle in this game is known for using lava to defeat Iggy Koopa. If Mario lands in lava, even if he has a Cape, he instanly dies. Enemies known as Blarrgs tend to lurk around in the lava.

Super Mario 64
Lava appears mainly on Lethal Lava Land and the ''Bowser in..." levels in this game. This game is known for the lava not defeating Mario on contact; rather burn him many times for damage until he finds a safe platform to land on. Lava is also used to defeat Bullys.

Mario Kart series
Lava is a hazard in some courses in the Mario Kart game. Whenever a racer lands in lava, they lose all their items and Lakitu carries them out. Also not as bad as the chilling water, lava and greatly send a racer back a few places. Lava always appear in Bowser's Castle related courses.

Paper Mario series
Lava minorly appears in the Paper Mario games. Much like from Super Mario World, if Mario lands in the lava, he bounces back out only taken one point of damage. Mario's partner Lakilester is the only one who can carry Mario safely across lava without harm along with Carrie.

New Super Mario Bros. series
Lava once again appears as a one-hit kill in the New Super Mario Bros. games. Lava is also used to finish off Bowser which, in turn, turns him into Dry Bowser. Lava also mainly appears in castle levels where Mario usually uses it to finish off Bowser Jr. or The Koopalings.

Mario Party series
Lava is usually used as a harzard to elimate players in the Mario Party" games. In Mario Party 7'', there is a Bowser event where Lava rises up in a certain area and the player that was on the platfrom loses all of their  Stars.