Basically a lvl up rb is a boss which:
Regardless of victory or defeat you gain (event currency to exchange) based on damage you dealt;
Everytime you kill it, it levels up and its hp and attack becomes higher (Stopping at Lv 30)
Raid points aren't used, but instead you will use (event currency to attack rb);
It will not escape overtime;
For each party, only five turns are possible, after 5 turns you will be forced to change the party to the next one;
Damage given is carried over
Unlike ordinary RB you can't request support, but you can bring a helper;
Solar blast can be used (Solar blast will also be strengthened if you choose 3x or 5x damage);
When you SKIP the solar blast will shoots automatically as soon it gets stored