I remember writing an essay on this, yeah, haha. The main issue is that even with Lex's defense boost, both Arthur and Tinny die in one hit when they are at half HP or below (especially if you reduce them to 1HP with the arena). This turns the Wrath gimmick into a very dangerous one: anytime it does not get the job done, you have a high chance of dying.
Examples of situations where Wrath/Ambush does not work:
- Ballistae
- Bolting/Meteor
- Enemy survives a crit
As a solution I've suggested using Prayer/Wrath instead by using Fin as a parent. It gets around the first two problems, and usually the third because Fin also gives both kids Pursuit and lets them crit the enemy twice. Of course, this comes at the cost of:
- Having to do math to make sure the kids enter a strong enough Prayer to survive reliably on the enemy phase you want to use them
- Having to do the above again and again
- Requiring you to go fast in Ch3 in order to get Fin/Tiltyu done
- No Elite for Arthur/Tinny, though I think the fact that Lex can now marry someone else and pass Elite there makes up for it
Is any of this worth it? Probably not. Azel/Tiltyu and Levin/Tiltyu both give you overall better results, but if you like Wrath combos and like to do mental gymnastics, I'd give it a try.