The fact that this game has no healer makes only a few teamcompilations really workable in this conquest mode.
To win a game you need to win:
bigger fights (3v3,4v4,5v5,)
small skirmishes
1v1s
basically there are only about 3 different teamcompilations:
1. Bunker teamfight compilations (without thief, for example 2 warriors, d/d ele, staff ele, guard)
2. Teams with a thief (should have a hard time vs bunker comps if played good)
3. movement teams (1 mes 1 thief)
I know there is more to that but I wont talk about this here.
So the fact that you have no healer means you have to sustain yourself. Means avoiding, blocking, neglecting, reflecting, interrupting damage on yourself.
Basically passivity is everything! The builds which deal damage while sustaining yourself are the best and will always be. The only other option if you are not as sustainable is to have more mobility to get away.
The team who sustains the more wins more it’s simple as that (assuming you rotate about as good as your opponent)
Let’s look at the current meta builds and why they are good and why certain classes are not so good at the moment.
Thief
Highly mobile. The thief has so much evade that he doesn’t really have windows where he has to decide “will i attack now or will i defend?” you just hit for a split second and evadespam again. So “passive” evading while dealing dmg. (I know it’s not really passive)
Warrior
Insane passivity. The heal is completely passive, you don’t need to do anything, it’s just there. With hambow you can neglect damage on the opponent (knocks) while dealing damage to him.
Eles
(not glasscannons). D/D eles and Staff eles have amazing sustain. Also everything somewhat passive. Heal is passive on usage, rest is on attunement switch.
Mesmer
Not passive. That’s why you have so less good Mesmers. You need to decide “will i attack” or “will I defend”. It’s somewhat viable due to max range spam and high mobility. The problem are thieves. You basically need a thief in your team to protect your mesmer. (the mesmer can’t disengage because he will loose vs the thief and then get stomped offpoint)
Ranger
Also has much passivity. Pets deal dmg, basically you can focus on evading and you win mostly. The problem with ranger atm is that he looses almost every 1v1 (vs eles and warriors which dominate the meta)
Necromancer
He has passivity but honestly not as much (a few traits). While fear is too strong (deals insane dmg while neglecting dmg) the necro is insanely weak. He has some kite mechanics (which don’t really work if there is no Z-axis). What makes him somewhat viable is that he can win 1v1s vs eles and thieves and mesmers and possibly also vs warriors plus he can survive pretty long vs 2 ppl with deathshroud and epidemic.
Engineer
Also has some passive skills but also not really much (burning is passive and bomb with evade). The problem with engi (and with necro) is that he has a huge windows in “defend or attacking”.