Gimmicks:
1 Servant will be assigned as "Attacker" and the other 2 will be assigned as "Supporter".
Attacker will have their Attack massively increased.
Supporter will have a Shield reducing all damage and regen HP every turn, in exchange their NP damage will be reduced significantly and they will prioritize using their support skills over attacking.
Breaking their HP bar or killing them will change the Attacker role to another Servant. This can also happen after a few turns with no death/break.
After break, Finn will give a random 1 hit Evade every turn to Bride and Nap, Nap will remove all defensive buff on your Servant, and Bride will give a buff to inflict burn on attacks to everyone.

Basically a reimagine of Taiga CQ. Having fun yet?

Note:
If you intend to follow this setup, aim for Bride on T1 instead of Finn. You can end the fight as soon as turn 3 this way.

#fgo