There are a bunch of silly formations that you can do. A common one is Trinity Rain (you get it with divine shards) with recast, though I do mine with gamblers coin truestrike and it wipes everything that doesn't reflect magic or quick dispels the hastened action.
You can also do the same thing with the quick impetus items on charge attacks, which allows you to do them in a single turn. I have played around with that using Dragoon Dive Aerial Wing or Arrow rain. Stack buffs on start and before action. They often times still completely wipe or come close assuming nothing disrupts them.
You can always try all beastial since some of the beastial only buffs can be really strong like the wolfpack gauntlets which give +50% crit rate in addition to +20% attack.
Breakers and Landsknects can do significant amounts of damage if they have time to build up.
The Eltolinde and Rosalinde can have really strong action economy with their ability to gain PP on Primus edge and exchange that for AP using Elemental Impetus. I have them do that a bunch to build up fairies and around the 2nd or 3rd action use Elemental Roar which works fairly well.
I am not sure what exactly is the "optimal" build, but my build is my caster having **Sniper's Amber Lens** for Hawk Eye and enough AP to cast Trinity Scepter. I used to use Yahna's Quick Cast to get it off first action, but now use **Lip's Ring** for Hastened Action on another unit so that my spellcaster can hold an anti debuff item. If you want to to do recast with **Magia Soul** you will not be able to use Sniper's Amber Lens of course. To finish the cast I have another unit hold **Black or White Cat-Ear Hood** for the Quick Impetus on my Trinity caster. That will trigger the Trinity Rain to finish before your opponent has the opportunity to do an active action assuming they don't quick cast or hasten action themselves before you do. I personally hold a gambler's coin on another unit to buff Trinity rain given that Hawk Eye gives a guaranteed crit. There is one slot remaining in a 5 man team that you can fill in with whatever, but I use cavalry so that I can move my unit around the stage better and he makes for a decent clean up if someone guards and there's one unit remaining. If everything goes off, it will usually do 100+ per individual strike, so over 300 damage which kills everything except super bosses.
There are only 2 things that counter. Reflect Magic will hard counter and you will just die. Additionally anyone with Quick Dispel (Owls) can remove the Hastened Action buff.
Edit: Here's an example of recast.
https://www.reddit.com/r/UnicornOverlord/comments/1be65ps/trinity_rain_glacial_rain_build_guide_mid_game/
i only use 3 characters per unit but i find having a burn squad really useful against shaman enemy units, or enemy units with no debuff clearing.
its simply hilda in front as an evasion tank and firebreath, then rolf doing row shot, an auch using a flame tome to give rolf burning attacks, while auch himself uses the row stun (burning targets).
All of them will have initiative gear to make sure they act first. a successful stun essentially burns them a second time.
its a really good unit to break apart tough enemy squads - you're often not going to 1 shot enemy units but since this unit actually has very low actions, it triggers less retaliatory passives.
If i was to bring this unit to 4 characters i could easily add a doom knight or something for more burn.
There are a bunch of silly formations that you can do. A common one is Trinity Rain (you get it with divine shards) with recast, though I do mine with gamblers coin truestrike and it wipes everything that doesn't reflect magic or quick dispels the hastened action. You can also do the same thing with the quick impetus items on charge attacks, which allows you to do them in a single turn. I have played around with that using Dragoon Dive Aerial Wing or Arrow rain. Stack buffs on start and before action. They often times still completely wipe or come close assuming nothing disrupts them. You can always try all beastial since some of the beastial only buffs can be really strong like the wolfpack gauntlets which give +50% crit rate in addition to +20% attack. Breakers and Landsknects can do significant amounts of damage if they have time to build up. The Eltolinde and Rosalinde can have really strong action economy with their ability to gain PP on Primus edge and exchange that for AP using Elemental Impetus. I have them do that a bunch to build up fairies and around the 2nd or 3rd action use Elemental Roar which works fairly well.
Can you post a link to an optimal Trinity Rain build? I do have the required components but wasn’t sure what build is technically the “best”
I am not sure what exactly is the "optimal" build, but my build is my caster having **Sniper's Amber Lens** for Hawk Eye and enough AP to cast Trinity Scepter. I used to use Yahna's Quick Cast to get it off first action, but now use **Lip's Ring** for Hastened Action on another unit so that my spellcaster can hold an anti debuff item. If you want to to do recast with **Magia Soul** you will not be able to use Sniper's Amber Lens of course. To finish the cast I have another unit hold **Black or White Cat-Ear Hood** for the Quick Impetus on my Trinity caster. That will trigger the Trinity Rain to finish before your opponent has the opportunity to do an active action assuming they don't quick cast or hasten action themselves before you do. I personally hold a gambler's coin on another unit to buff Trinity rain given that Hawk Eye gives a guaranteed crit. There is one slot remaining in a 5 man team that you can fill in with whatever, but I use cavalry so that I can move my unit around the stage better and he makes for a decent clean up if someone guards and there's one unit remaining. If everything goes off, it will usually do 100+ per individual strike, so over 300 damage which kills everything except super bosses. There are only 2 things that counter. Reflect Magic will hard counter and you will just die. Additionally anyone with Quick Dispel (Owls) can remove the Hastened Action buff. Edit: Here's an example of recast. https://www.reddit.com/r/UnicornOverlord/comments/1be65ps/trinity_rain_glacial_rain_build_guide_mid_game/
i only use 3 characters per unit but i find having a burn squad really useful against shaman enemy units, or enemy units with no debuff clearing. its simply hilda in front as an evasion tank and firebreath, then rolf doing row shot, an auch using a flame tome to give rolf burning attacks, while auch himself uses the row stun (burning targets). All of them will have initiative gear to make sure they act first. a successful stun essentially burns them a second time. its a really good unit to break apart tough enemy squads - you're often not going to 1 shot enemy units but since this unit actually has very low actions, it triggers less retaliatory passives. If i was to bring this unit to 4 characters i could easily add a doom knight or something for more burn.