Mystery Dungeon - farmable OP runes

[KFCrispy]

You can farm Rune of Warrior's Pinnacle and Rune of Mage's Pinnacle, which is basically the Fury Rune from the Suikoden games. As long as you're fine with resetting your progress in the Mystery Dungeon (at some point your progress will save, so I think it's harder to farm for specific when continuing progress).
If you haven't tried it, fighting in Mystery Dungeon will inflate your team's levels as well, so even if you don't go for any specific rewards, fighting enough in Mystery Dungeon will have you steam roll the rest of the game.

Warrior's Pinnacle is rewarded from Ancient Seed. It boosts STR for the first 4 turns.

Mage's Pinnacle is rewarded from Astrea the Judge. It boosts MAG for the first 4 turns. Recently I found out the characters who attack with a magic element use their MAG, not STR, for normal attacks! Mages with high MAG and this rune will normal attack for huge damage, and a basic spells that deal "moderate" damage do even more.

[Julian]

The sniper version of the rune seems to give 100% crit rate.

These 3 status effects are the same status effects you get when certain other "comptabile" units die, similar to someone berserking in Suikoden when a friend dies. That version only lasts 3 turns, though. (Allegedly, maybe that means it lasts 3 turns, then expires at the end of the 4th rather than the start of the 4th? Not sure...)

Also, the effect of these two is +50% power and +50% magic respectively.

[KFCrispy]

Thanks, I was actually wondering if the effects doubled the respective stat, because sometimes it felt that way!

[KFCrispy]

It's possible these easy rewards have been removed after the recent patch.

[Monkquistador]

Still working. Getting all drops, resetting to get specific boss prior to farming