So, like, what is so good about Faris' BSSB? I just got it on my 100 gem.
I'm actually assuming you're trolling as it's directly after my post praising it to the heavens...
But just in case your not trolling and didnt take the time to actually look at the relics description before posting directly under a gigantic explanation of how class it is... The main attack is a 5 hit Full Break. (Aka, no need to bring it, saves an ability slot) The burst commands are Magic Breakdown (Aka, no need to bring it, saves an ability slot) and Power Breakdown (Aka, no need to bring it, saves an ability slot...I shouldn't need to keep repeating this but you seem to have overlooked it, and you may notice if I mention it each time) It's a bow so it can be used from the back row. Its quite strong, also adds magic and mind (so well rounded in general and very useful for flexible characters like Tyro/Onion Knight/Bow mages) silly not to Rosetta stone the bejeesus out of it and use it in most realms with Faris herself. Faris as a character is as flexible as fuck, has decent equip options and can self boost with the 6 star thief skill Mug Morale that arrives soon (it only needs to be R1 and just clearing the event it arrives in allows you to get a free copy) so can be physical and keep an enemy broken in mage teams and in shout teams IT STACKS because its a combined armour/power breakdown so she caps damage even against most Ultimate++ bosses (note that there are two pluses, we don't even have those yet)
Ramza who I have with shout in global can only pack full break and one other breakdown. Faris with her BSSB has all three and two free slots. If I pulled her BSSB in global Id bench Ramza and RW shout.
...she lacks life siphon but it doesn't matter because throw Mako Might on her and all you need to do is Mug morale (shout will be up by now) then 5 hits of between 5000 to 9999 each and then pretty much 9999 damage breakdowns on everything up to U+ level (and often in U++ with good synergy) until burst wears off then repeat, with the possibility of thief's revenge in between to heal or do a bit more damage if there's breathing room...Boss defeated. Most bosses don't last through more than two cycles of this unless they have insane defense/HP or different mechanics, and in that case all you're losing out in is not being able to drop another Mug Morale in between if its R1...but guess what? Its possible to R2 it if you invest the resources from that event a certain way if you really wanted too...
Anyway, out of interest I'm going to do motte Ifrit as its open again in Japan and report back damage findings to put it in perspective...I walked through motte Ifrit first time in Japan primarily because of this relic. In global I still haven't beaten it with a native trinity...
In short... What is so good about it? Everything.
EDIT: As mentioned above Minfilia's BSB has finally arrived and is now one of the few things with a similar function and more than likely does more damage from the SB itself and the burst commands...but it doesn't come with full break, so even seemingly direct replacement 6 months of power creep down the line still doesn't cover all that Faris' does...she might finally get the boot if I got that relic...but its no guarantee.