This party is great for racking up Flawless victories even against big enemy parties on Veteran/Expert. I wouldn’t use it in survival mode, though! Equipment is a little vague; I don’t afk-farm survival mode so I’m still working on collecting all the purple items. The key is order of action (Warrior first (!!), Mage last) followed by damage output.
Formation: Captain front middle, Marksman and Assassin on front flanks; Conjuror back middle.
Warrior – Captain
Equipment: Relentless, Annihilator set, anything with quickness/starting action/strength/crit (in roughly that order). A 5-point Annihilator set plus Fallen Legion Epaulets or one of the pieces with a starting action bonus would be ideal.
Stat build: All Strength
The Captain’s job is to hit first and put Inspiration on the rest of the team. To that end, he needs to be the fastest member—not the easiest thing to achieve on a Warrior (without sacrificing damage output). Relentless (the two-handed sword with +5 quickness) is the key item here; you get the power of a two-handed weapon with what is effectively a mammoth 10-point Quickness bonus (comparing it to other two-handers which are all -5) The +4 Quickness from a 5-point Annihilator set is great too.
Ranger – Marksman
Rogue – Assassin
Stat build: All Dexterity
Style: the Marksman switches between Hunter’s Focus and Marksman as needed (i.e. switch to Marksman only when you actually need the extra damage or accuracy to make a kill, so you aren’t eating -5 quickness all the time) Likewise, the Assassin switches between Poisoncraft and Deadly on a situational basis.
These two characters are simple damage dealers. Equipment is whatever you have that maximizes damage output while preserving the desired Quickness order. The Marksman should be a bit faster than the Assassin so that you can use Pin + Coup de Grace on annoyances like Thralls (whose combination of high Quickness and high HP makes them one of the bigger obstacles to getting Flawless wins) For the Assassin the Prowler set is optimal for damage output, but the 50% starting action from a full 6-point Prowler set will almost certainly make him faster than the Captain, so go with 5-point Prowler plus something like Blackheart’s Mask.
You might try replacing one of these two characters with an all-Intellect Inquisitor, but making a Cleric fast is even harder than making a Warrior fast. Litany of Pain with a Magma Torch is something I’d like to try…
Mage – Conjurer
Equipment: Whatever maximizes his damage output (i.e. Intellect gear, mainly) while keeping him slower than his teammates but faster than the bad guys. The Omniscience set is better than the Aetherweave set for him—it gives more Intellect, and the Aetherweave set’s fat Starting Action and Quickness bonuses are something you don’t want with this party (unless you have a lot more Quickness gear on your other three men than I do)
Style: Channeling, unless that makes him faster than one of your other members, in which case make one of the other styles default and switch to Channeling on his first turn.
The Conjurer’s job is to cast Time Warp right after the first three characters have attacked, effectively giving you another full round of attacks (at +15% damage!) before the enemy can do anything. Then he starts blasting things.
If you plan your kill order carefully, you can get a Flawless on almost any enemy group in the game. Even if something slips through (you whiff an attack, or you just don’t have quite enough firepower to kill everything) the damage you should take is minimal.
This party has no defence or staying power to speak of (it’s pretty much screwed if someone gets stunned or gets quickness-debuffed, thus messing up your turn order), so chug Alertness elixirs before tackling ambush rooms, and watch out for terrain. If you have to change from a “T” to a square or “Z” formation in order to avoid bad terrain, the Conjuror is the character who should give up Inspiration, since he spends his first turn casting Time Warp instead of attacking.