Mount Training (v-25-1500 return) – 3 days: Train mounts in the Stables. A good event giving a lot of Whips back. Includes 2 x 5 Cast Stones in the first 2 tiers.
Mount Refining – 3 days: Refine mounts. Includes 2 x 5 Cast Stones in the first 2 tiers.
Divinity Soul Synthesis – 3 days: During the event, synthesize Level X Divinity Soul(s) to receive rewards. Level 5 to Level 11.
Holy Water Sipper – 3 days: Use X Golden Holy Water to receive rewards. Includes 1 x 5 Cast Stones in the first tier.
Sylph Equipment Enchant – 3 days: Enchant Sylph Equipment X times to receive rewards. Includes 2 x 5 Cast Stones in the first 2 tiers.
Sylph Enchantment Exchange – 3 days: Exchange Event Chests for various sylph equipment related items. I do not recommend to do most trades in this exchange using event chests which are better used elsewhere (however if you happen to have tons of mini-items could use those perhaps).
Holy Sword Leveling – 3 days: receive Polishing Orbs for achieving various milestones (one time per lifetime rewards).
Bad hackers can make “from” email address look like anything they want. If you receive emails from COSMOS/DolyGames asking for your account details or password or money or anything strange – these e-mails are a case of criminal phishing and should be ignored.
Be careful, also for your personal emails, good luck!