Hello

Just wanted to say lifesteal is very much a big deal in clan boss, there have been teams built where there isnt a main healer and all healing is done by fast lifesteal champions, for example tayrel does really well with lifesteal and since he is defence based also last a long time. 

Honestly i was asking myself the same questions, all my main champs run basic sets, most if not all have base speed of 220. 

This question to me can have a very detailed answer due to what champion your gearing, so im just going to throw out some things i have used and see used well

Reflex, amazing for champions with 2 skills, like skullcrusher or bad el kazar. Hitting off a move a turn early can prove to be awesome, i am looking to build a very speedy verions for my bad el kazar. (Clan boss)

Retaliation, great on champions that you really want to push their first moves more, or vrask ;), this allows more opportunities to apply debuffs that champions have on thier basic move, much like tayrel, crimsonhelm etc (arena and clan boss)

Frost set, this goes great on defence based champions or any champion which can take a hit, fantastic in arena to stop the 2nd runs when running a survival team(hp or def) (arena), you probably know this already but just note frost reduces your damage onto that target.

Toxic, throw this on a champion if you dont have any posion champions already and watch you damage jump, i used this on cold heart to apply posions. (Clan boss)

Shout out to crit dmg set(though its basic) this set is amazing, the right build can send you over 260% crit dmg. (More arena)

Stun, this is a good set but it can be a hit and miss, best used on anyone that has a move that attacks all targets.

Been using alot of immortal and cruel(2 piece sets) abit lately, though these are like the basics.

I hope i might of given you ideas there, or something to think about.

Regards

Thanks for the feedback. Good to know that there are a good handful that are viable, even at the higher-end. I wasn't sure if we ended up getting funneled down to specific ones that were particularly favorable. Seems more than anything, it depends on the group.

The lifesteal concept for clan boss would be great if I didn't have Pain Keeper. With her cooldown reduction skills and heals that literally top off my entire group every time, it's hard for me to go to any fight without her. :)

While I don't have one yet, I am hoping to build up a poison artifact set or two later on. I figure since it is % based, it could prove to be amazing for bosses at the higher tiers.

For arena, I prefer flat out speed and offense, along with a little accuracy. I don't like how crits are not always reliable, and flat out increases in attack are beneficial and reliable in any encounter. This combined with speed so you make the first attacks and don't have to worry about debuffs (or resistance for that matter) is something working out very well for me so far.

I have found life steal to be extremely viable in arena too. It keeps champs with mid lvl hp/def topped off because these are my higher attackers. It's not the best on the glass cannon types just because they normally get 1 shotted before the chance to heal themselves so stacking some hp is the better trade off. It's also not great on tanks because they normally don't hit hard enough to heal enough to waste the space. 

Frost sets are amazing on your tanks in arena, even better if they have taunt. If you've never faced one in pvp when you do you will see the lvl of frustration they can cause. I've had it proc on almost every time Ive attacked. It really will drive you crazy and get you killed. 

I do love toxic, I even have one on one of my kaels. It helps to keep all 10 stacks of poison up more often. Don't recommend it outside of cb teams, as it doesn't do enough dmg elsewhere.

I have mixed feeling on relentless set. I only use it on 2 champs that are on my fireknight team. The proc is very unreliable. Sometimes it will proc over and over and I'll clear it in 3-4 turns. Other times I'll go multiple fights without ever seeing it proc at all. 

Retaliation has a bit better results but I still don't use it enough for similar reasons. I prefer something more steady to rely on. Others may disagree and enjoy the gamble with these sets.

A single shield set is nice to defend againts the first turn burst of other teams in arena as it buffs before any action takes place so even if your team is slower you'll have the protection.

I'm just starting to play with reflex, using it on champs that don't have an active a3 so you always get the skill you want to refill is great.

The extra heals in cure is something else I'm starting to try out. So far I'm on the fence about it. 

Frenzy is interesting as every 50% hp lost you get a free turn. That seems more reliable that retaliation. I haven't wanted to sacrifice a champs slots to run it yet, but I keep wanting too.

Fury also seems cool, but again I'm not brave enough to try it. 

I used cursed quite a bit on spirit keep before I got a more reliable heal reducer. 50% reduction is enough to get the job done, and it proc on any ability you use. Once you have a good 100% reducer I don't see the use.

Stun, sleep, max health reducers, dmg reduction or counter on aoe I don't think are viable to waste a slot on. 

Now that faction wars are here, I'll find myself using these sets more to fill gaps in team powers. Like I'm sure cursed will become needed again ect.

I of course think Savage, cruel, the Divine sets, immortal, ect. Are all part of my normal rotation.

I hope they add some sets, ones that can dispell Ally's, or remove buffs from enemies. Ones that reduce emenies turn meters by at least 40%. Any even ones that buff the Ally's. These will become favorites when working within faction wars. I'm finding myself to be lacking in arenas of certain factions, gear would fix that. 

I also think the sets I mentioned as not being viable they should consider making sets of 2 so they get more use, or even sets of 3, then you could use 2 of those sets at a time. Possibly making the gear that carries buffs and debuffs like I mentioned we need could also be required in sets of 3. It would make those sets much more circumstancel which will be fine for faction wars. 

Wow,  you dug up a really, really old thread, lol.

I've learned a lot since this, so let me throw this out there real quick:

Clan boss - Ideally, you want a lifesteal set and speed set.  If you are running a counter group and can get up to the minimum speed for your respective boss (171 for NM or 191 for UNM) without a speed set, then you can load up on more defense with a defense set, more hp with an immortal set, or otherwise have more options depending on that champion.  Some people even go with a crit rate or crit damage set along with it, as those will help you heal with lifesteal anyway.  But, lifesteal is a staple in any group.  Once you combine it with warmaster or giant slayer, it's just way, way too valuable for topping off your HP.  You don't even need a healer with it.

Arena - If you want to get in gold IV, you ideally want a speed team.  One champion should have a speed aura, and you need someone on the team that has a turn-meter boost to get everyone else a turn before the enemy.  I can tell you from personal experience, when I went from a glass cannon team with atk % aura, to a speed aura with High Khatun, I went from a low gold team (gold I), to gold IV immediately.  Speed always has the upper hand.  Once you do have that, like Erikbogart said, you have more choices.  Frost on a champion you know they will target, like your healer or ressurection champion (like say Gorgorath) can be great.  Otherwise, I suggest glass cannons to kill, modest accuracy on your debuffers (def down, atk down, provoke, etc.), and speed.  My videos from when I changed up speak for themselves.  Just watch the ones where I still had Inithwe in them (atk % aura) to the ones with Khatun in them (speed aura).  It was a world of difference.

Dungeons - This is where things get a lot more complicated.  The ideal sets in here will really depend on the champion and the respective dungeon.  Depending on the champion and your team composition, quite a few sets could be good.  Let me just name them off here:

life set - inferior to immortal and divine life.  only choose life over one of those two if the other stats are much better

offense set - again, inferior to cruel and divine offense.  only choose if the stats are much better. also, crit rate and crit damage are FAR more valuable in this game than raw atk

defense - viable

critical rate - viable

accuracy - viable

speed - viable

resistance - rarely viable.  sometimes useful on your lead champion (tank) on Spider dungeon, but usually not very good unless you have a champion with a strong taunt or otherwise getting attacked more than any of the other champions

crit damage - viable

lifesteal - viable anywhere.  again, once you have warmaster and giant slayer, this is a great set.  the only exception to this is if you have a healer or other type of champion who has lots of skills that don't tend to attack or otherwise damage the enemy.  if you aren't attacking much, obviously this set won't do much good.

destroy - complete garbage.  NEVER useful anywhere.  the numbers just aren't significant enough.

retaliation - VERY rarely useful, unless the champion has an AMAZING A1 and/or is a tank that gets targetted a lot and it would be reliable.  Someone like Bad-El-Kazar could use this with great efficiency in dungeons, but there are few champions where this is viable

fury - RARELY ever viable.  it would have to be VERY situational to make it worth it, as it is inferior to crit rate or crit damage, which aren't dependent on you losing life.  Only champion I am thinking of that it could even be remotely useful is Skullcrown, but even then, I believe other sets would be preferable.  *Might* be useful on her in arena on a defensive team, but I discourage defense teams, so I really just don't suggest it.

curing - complete garbage

reflex - rarely useful, unless the champion has ridiculously powerful cooldowns, like maybe Roshcard or some other OP champion.  it's too unreliable at only 30% and with a *random* skill, so might not even reduce the one you want

cursed - VERY situational.  if you have a solid team for say Fire Knight Castle, but no one on that team that prevents healing, then this could be a solution.  otherwise, it's just not very good.

toxic - complete trash.  2.5% poisons are just way too weak.  they take up a slot that a 5% poison could.

frost - as erikb already stated, can sometimes be useful in arena with a defense team, or possibly in dungeons where you have a champion with provoke or otherwise tanking the dungeon.  But again, I do NOT support defense teams in arena personally, so really just for a select few dungeons with the right champions that you KNOW will be getting attacked over your other champions.

daze - garbage, since as soon as the target takes damage again, the debuff is removed

immunity - garbage.  this would again be useful for an arena defense team, but once again, i do NOT advise defense teams over speed teams.  in dungeons, your teams *should* be so much faster than the enemy that it will most likely drop off before it ever even serves its purpose.  *maybe* if it lasted like say 4 turns, but then it would be VERY OP in arena

avenging - retaliation is FAR superior to this.  garbage set

shield - garbage.  again, only use would be on an arena defense team

stalwart - garbage

frenzy - garbage

regeneration - inferior to immortal.  unless the stats are amazing on it, it's trash

stun set - useful for champions with LOTS of AoE attacks, like possibly on Bellower, Psylar, or someone like that

relentless - inferior to a speed set and too unreliable.  only use it for long-term encounters, where you have better odds of it occurring, and only if the stats are MUCH better than your speed sets

savage - this could be good on your high damage dealers, but I am unsure if it is up to par with cruel sets or not.  have yet to do the calculations on it, as i have never farmed for it (I tend to farm dragon dungeon, as the overall sets there tend to be more useful for me)

taunting - rarely useful.  at 30%, too unreliable.  unsure though if the taunt is attack based, or hit based, meaning if your champion has a 4-hit A1, if that would be four 30% changes, or just 30% for the attack itself.  either way, still too unreliable to be viable, save for *possibly* some very rare situations where you need that champion to tank as much as possible

cruel - GREAT set.  other than your speed aura and turn meter booster in arena, this is the MOST valuable set in arena, at least on most champions.  with 3 cruel sets, you ignore 15% of the enemy's defense, PLUS you also have that extra 15% attack on top of it.  only others that could potentially be better would be crit rate or crit damage sets, depending on the stats on the artifacts

immortal - GREAT set for HP or defensive champions.  with a full 3 sets, that's 9% HP healing every round on top of the extra 45% HP the sets would offer.  great for champions whose healing is based off their HPs, like say Pain Keeper (although after the nerf in 1.8, she is fairly worthless in end-game content, save for with champions with EXTREMELY powerful cooldowns.  even then, she is unreliable, as you can't count on her casting A3 at the ideal time when it comes to auto-farming)

divine life - better than a life set, inferior to an immortal set.  only exception would be an arena defense team, but you already know how I feel about them.

divine crit rate - better than regular crit rate, depending on the stats on it.  unless the stats are better than on crit rate, I wouldn't suggest it

divine speed - better than regular speed, with ONE exception - if your masteries include the support tier with the added stat bonus from "lore of steel", then unless the stat bonuses on this are better than a speed set, prioritize speed sets

-------------------------------------------------------------

Two things to add here...

1)  Prioritizing a set over the stats on the gear is not always the best decision.  For instance, if you need crit rate, but a frost piece and a cruel piece combined offer 35% crit rate between the two, and you have a crit rate set that only have 13% combined on them, then it would be better to choose the two that are not part of the set, as even with the set bonus, the crit rate set would only offer 25% compared to that 35%.  So, if you have an off set that has some REALLY amazing stats, might want to do a basic number crunch.