With season 3 being announced and bringing along a new legend (Crypto), a new battlepass, a new weapon (Charge rifle), and new stuff we don't know yet but I would like to talk about the name because the name could point to what's happening with the arena and the lore surrounding it but first let's take a look at previous season's names to see how they correspond with the season they were attached to.
Season 1 Wild frontier: the first season as we know didn't bring much to the table besides Octane, a not so good battlepass, and no changes to the map but in the season 1 trailer towards the end you can see flyer's flying so alot of the community speculated that they were supposed to be brought in that season but they didn't till season 2 so the season name (wild frontier) didn't do anything that wild but season 2 changed…
Season 2 Battle charge: Battle charge means two things in this context, Wattson and the leviathans. The leviathans walked in the arena and destroyed several places and now they rest in the middle of the map. Wattson is the latest new legend and her thing is electricity and defense with her pylons and trophy system. Since season 2 started there have been new events which brought new places in the map with the gauntlet and labs which are characters specific places.
Season 3 Meltdown: Now with the upcoming season we know that Crpyto, charge rifle, and a new battlepass are coming but there have been leaks and in game lore to point out what's happening. First with the leaks: there has been a leak which is a pve mode where you have to collect some collectables type things and there will be hostile ai creatures like the prowler which has not been in the game yet and there also has been a Halloween type pve event but that's all we know. Now with the in game lore: with the teases with Crypto in game like hacking the announcer's and other things and also recently at labs you can see him hacking something then he leaves but you can see on a monitor with some text with the words "World's edge". Now people has been speculating that this means he'll bring up a portal to a new map or bring something here in Kings Canyon. This is all we know about season 3 right now.
Other: The name Meltdown could refer to a volcano or lava invading the name but I personally think that Crpyto will hack something (like a hidden reactor or the labs) which will "Meltdown" which will cause the portal or a new portal to bring new things from another place or dimension in the map with new ai hostile creatures destroy already existing places or bring new places.