I'd really like the idea of a larger LMS game style, thinking of the current battle royale's out there, like apex legends or warzone.
The map would be a lot larger than the current ones, think the size of mainland RS, I am hoping the games will last around ~30-40minutes if you are in the final area / winner.
It should include some pvm / looting elements for at the start and through out to get some initial upgrades / potions / food. This could include some monsters to kill. Some skilling elements such as pickpocketing some npc's or chests.
Then the gas will push people closer together as the game continues, ideally the zones would be marked on the minimap however I am not sure if that is plausible / would need engine work.
The rewards could be a large amount of LMS points, however ideally it would include some other things and the winner could have a title / skull above their head until the next event happens.