Arena of Dischord (Elemental Battlefield/Original)

In this arena, the elements seem to be at war with each other. Watch where you step!

Monsters
None

Gimmicks
Every four turns, lava rocks (summoned by the element of Earth) rain on the battlefield. Anyone hit by them takes 5 damage.
Every six turns, large ice boulders (summoned by the element of Water) fall onto the battlefield. Anyone hit by them takes 10 damage.
Every 10 turns, two of the four subsections of the arena burst into flames (summoned by the element of Fire). The sections are randomly chosen, and anyone burned takes 10 damage.
Every 15 turns, lasers (summoned by the element of Air) fire at the arena in a straight line from various cannons on the side. The lasers that fire are randomly chosen, and anyone hit takes 5 damage.

Map
(-)(L)(-)(L)(-)(L)(-)(L)|(-)(L)(-)(L)(-)(L)(-)(-)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(L)
(L)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(L)
(L)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(L)
- - - - - - - - - - - - - - - - - - - - - - - - -
(L)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(L)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(L)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(L)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(-)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(L)(-)(-)(-)(-)(-)(-)(-)|(-)(-)(-)(-)(-)(-)(-)(-)
(-)(-)(L)(-)(L)(-)(L)(-)|(L)(-)(L)(-)(L)(-)(L)(-)

L=Lasers
Red=Lava Rocks
Cyan=Ice Boulders
Indigo=Both
|/_=Dividing Lines (for Fire-based gimmick)