1/ Implement seasonal tides: water levels will vary depending on the season. It should not be a major variation, just a bit to change the landscape.
2/ Poisoned weapons: using goo or loot/forage ingredients
3/ Sickness event: I played such an event in Regnum, years ago, it was quite exciting and interesting. A type of creature (low level) will be spreading in Atys, very aggro, and giving a sickness in n% of the cases. This sickness will provisionally decrease your (health/sap/stamina/focus). Remedy can be found or purchase. I guess the RP could be quite interesting. (Silan has to be left uncontaminated)
2/ Poisoned weapons: using goo or loot/forage ingredients
3/ Sickness event: I played such an event in Regnum, years ago, it was quite exciting and interesting. A type of creature (low level) will be spreading in Atys, very aggro, and giving a sickness in n% of the cases. This sickness will provisionally decrease your (health/sap/stamina/focus). Remedy can be found or purchase. I guess the RP could be quite interesting. (Silan has to be left uncontaminated)