I have been farming events as a lv11 like a year and i can tell u this is prob the best for events

Passive: H Samael ( Cuz my fav pet ik there is better pets :P)
HB: Arc Bemine ( Cuz gives high stats dmg and speed stacking)
AA: Cotis ( Cuz toxin aoe dmg kill all mobs rly fast and u can use this for farm rly fast energy too)
Harpo( This pet rly good for bosses. Only recommend u to use for winter event siry boss die rly fast if u have a partner with this pet too)