A stronger, more emphatic variant of 'llueva o truene' used to stress absolute determination that something will happen or be required regardless of any imaginable circumstance.
Examples:
ES: Así llueva, truene o relampaguee, mi ramera debe tener mi dinero.
EN: Through rain, sleet or snow. Brother's a Shakespeare! - My ho better have my money.
ES: #Sigo luchando llueva, truene o relampaguee
EN: So, I stay on the grind, rain, sleet, hail, snow
ES: Estoy contigo llueva, truene o relampaguee.
EN: Baby, I'm a ride-or-die bitch. You know that.
ES: Solo quiero que sepas que, llueva, truene o relampaguee, vamos a casarnos hoy.
EN: Uh, I just want to let you know that, come hell or even higher water, we are getting married today.
ES: Mellie, te voy a poner en el despacho oval, llueva, truene o relampaguee.
EN: Mellie, I will get you in the Oval, come Hell or high water.
ES: El pago se hace el primero, llueva, truene o relampaguee.
EN: Payment's due on the first, rain or shine.
ES: Vamos a terminar, llueva, truene o relampaguee, antes de fin de mes.
EN: We'll finish by the end of the month, regardless of what happens.