Optimizing crit on Hayato

That, on face value, is fairly significant. But first I need to know 1) what ring you plan to replace if you use the crit ring, 2) if you have any other sources of crit damage e.g. character card, link skills (can't remember if there's one for this) etc., 3) how much total WA you have, fully buffed with standard stuff only. Also, if you could find out what monster type the Lapis Renewal has bonus damage on?

Hadriel

The ring will replace an Evolving Ring I, so I will lose 7 all stat and 3 attack. My only other source of critical damage is Hayato's character card that gives 6% minimum critical damage, and Unfaltering Blade which gives 25% min/max crit damage. I have 295 total attack currently (not using the Loveless katana yet), but I should have 338 total attack afterwards, all with normal buffs. I also see that the Dragonic Lapis Renewal does bonus damage on Mammal-type monsters, but I'm not sure about the regular version, sorry.