you are actually supposed to start with the most/strongest element relics that you have.
Get the magicite, raise the level then go on to the next one in the clockwise direction as the magicite will help you with the next one.
I was just testing my luck with Fenrir.
If doing the Cloud OSB way, you'll need to USB > OSB > OSB > USB... best if you bring Zack's Lucky Star to boost 20% too (even tho it's hitting with non-elem, you will still get the boost, because your attack is wind/non-ele).
Got my ass kicked v v hard when doing Bismarck even though I have some lightning BSBs
If you don't have, or don't want to rely on relics/SBs, you can hone multiple 5* ninja skills instead (e.g. Raging Storm + Gust for Golem).
Bring in a ninja team and you can kick ass and maybe even do it within 30 secs.
The skills are stronger than using SBs, and no need for en-Element, imperils etc.