"The Floor is Lava" Gamemode as an Event in TTT

I want to script the Gamemode “The Floor is Lava” as an Event in my TTT Script. It shall work like the Gamemode: When the Event starts, all over the map shall spawn Lava and with every second the lava shall rise up to the sky. If a player touches the Lava, he shall burn and die. I want to know: How can I script this ?
Thanks in advance.

Hooking into

GM:OnPlayerHitGround should be all you need.