Obtained through rare RNG, grade 5 OoS emissary or bought for gold from the Order. A small purification gem would be used on islands the temporarily prevent skeletons, phantoms and ocean crawlers from spawning.
The ritual could be as simple as placing the gem into a spot on the shrine and "hey presto" or placing the gem could spawn a few waves of enemies with the boss dropping the final gem to complete the ritual. Once the ritual is complete, perhaps some indication that the island is "safe" such as a beacon or a light mist surrounds the island (maybe the mist doesn't let you see out but other crews can still see you on the horizon.
I think a feature like this could be quite fun for crews as it gives them not only something to do but a reason for doing it beyond loot. Maybe the crew wants an island to bury their loot or has planned to use the nearby pond to do some fishing or maybe multimedia crews have gathered for some wholesome RP and minigames but they don't want to deal with mob spawns every 30 seconds. So after a small task/fight they are allowed a moment of respite, at least until the ritual effect wears off.
please comment with any suggestionson how to improve the idea
