1.S rank (year) weapon skin box
this box let us choose a weapon skin from all skins on sale during (year) period.
2.annual event:goddess anvil blessing
per year, on a specified date and time, grant all players a 5 second(or more) buff that increase anvil success rate to 100.literally +1 or +2 perhaps a year. if +2 or more is excessive reduce the duration but dont forget some players suffer from RTT,lag etc.
3.annual potential restoration potion
back then we got a +1 potential restoration.that was very nice but i think give +1 to all gears in game is kinda excessive. maybe once a year, give 1 item that restore gear with 0 potential.if tradability is an issue, then dont restore the tradability state.