Nothing's better than a new minigame in runescape. Well, runescape has done better in the recent months with consistent game updates. But rs gold players have more creative quests they like to be put in the game. If good enough, it is possible to see them in the next update.
The quest we have today, Beaver Apocalypse, would be about protecting forest from beaver horde, that would lay waste on it. It would involve fighting beavers, planting new trees and cutting down damaged ones, and building battlements against beavers.
Herblore would also be in game. Players would need to gather plants from forest to make potions to cure damaged trees, they could also make evil sauce and put it on decoy trees to make beavers eating it sick.
Hunters could make different traps to halt advancing of beavers. It would be different from games like Pest Control as tendering, and planting trees would be as important as fending off beavers.
In first phase, there would only come beaver workers, that would be weak fighters, but destroy trees if they get their teeth on it. In second wave, there would be beaver berserkers, soldiers and workers. Berserkers would be all about combat, soldiers in between them and workders in both fighting and cutting.
In the last wave, there would be all beavers and beaver king, game would end when forest is lost or king is slain and beavers would retreat. Rewards would include beaver costume that would offer WC bonuses and of course xp in all skills involved.
This could also be basis of the quest if minigame is too much for beavers.