Come rain or shine
omikrontonos ti ke na jini
In Greek Ό,τι και να γίνει
This phrase is used to express that something will happen regardless of the weather or any other circumstance.
Example
"Θα είμαι εκεί, ό,τι και να γίνει (Tha eímai eké, ó,ti kai na gíni)."