TL;DR: For people asking whether they should mtix Yamaraja: IMO don't.

I agree that Amaterasu is in most situations better than Yamaraja. Yamaraja is not bad though. 700k nuke every 6T, ATK/DEF/combo rate debuff and sometimes useful affliction block (extremely useful for this raid rag challenge). Not saying that I would recommend mtix'ing her (because I wouldn't), but don't undersell her that much.

And now some other nitpicking:

Quote Originally Posted by Slashley View Post
Def Down: SSR grade is -20%, effectively 20-28% more damage, 8 turn CD for 180 seconds = lasts enough for full uptime. About 20~28% more damage (20% more when going from 0% Def Down to -20%, 28% when going from -30% to -50%).
Effectively 25~40% more damage.

Quote Originally Posted by Slashley View Post
It's not even a contest. BUFFS ARE SHIT. The only time when buffs start becoming a part of the equation is when we start getting bosses which are highly resistant to debuffs, which will supposedly happen later down the line (as soon as next event?).
No. Buffs are part of equation, when they are good. Like for example some stackable buffs, AW Shiva buff, Thunder Aphro Vigor buff.
Agree that Yamaraja's 15% ele up is hardly her selling point though.

Quote Originally Posted by Slashley View Post
Come on. Just fuck off already and don't waste both of our time.
Calm down a little here.

Also, ability damage does not suck and even in future meta it's quite important part of overall damage in some teams (and I am kind of ignoring rage control aspect of abilities here).