I'v played a couple of games with erebus and love the mist ability. With my item build I am able to regen full health while in mist mode and at the same time deny kills.

As much as I like it, I agree that it needs a nerf. A short cast time may do the trick but a mana cost would make the ability useless ealy on.

Mist is only useful for the invulnerability, the DPS is terrible. Its much better than Oak's shield, it has no time limit (at high levels with mana regen items) a much lower cooldown and at later levels it acts as a full heal. The only negative is not being able to attack or move. Since shield is a defensive mechanism, rather than offensive, that isn't so much of an issue. The problem is, if you remove the invulnerability it becomes useless. Alternatives which would still make it useful would be to either:

i) remove the heal regen (so you exit mist with the same HP as you entered)

ii) make erebus vulnerable to AoE damage spells while in mist (spells, not skills - ie hammer slam shouldn't effect it (how do you hammer slam mist) but fire AoEs should)

iii) make erebus vulnerable to AoE interrupts (to knock him out of mist)

iv) as suggested earlier, allow DGs with truesight items to hit him. However, unless the price of these items increased, this would make mist useless.

These all keep mist useful, without giving erebus a 1 click invulnerability button for whenever he's low on health.

The Lord has a disadvantage when in Myst there is no support for the team and he can't move.

By playing against good players, Myst is useless without support. Just wait until the Lord comes out of Myst and kill him.

I'm in the same player group as Kayato (the main Erebus player among us)

Erebus currently has great survavibility and is safer than most when retreating. But mist can be somewhat of a trap, and I've found myself waiting to slam the vampire face just on the mist border, in more than an occasion.Not to mention a muist relying vampire don't have much of an impact on the game. His army can be dispatched in the meanwhile, you can drink potions/use trinket/invoque your minions/use light tower/mines while waiting for the return of Erebus. He can only gain HP and loose mana.

BUT... since it allows to reset the cooldown of bat swarm/wand of speed/warp stone, it can be a very powerful evasion tactic. Best tactic remains laying shrapnel mines under his feets. Maybe the cooldowns should be halted while in mist form. Or at least increase the mist cooldown itself up to 20s.

The mana pool may be the real issue, with most demigods. It's not too difficult to get enough mana to not think anymore about it at later stages. Helps to make the game more dynamic but is a bit too powerful with short CD actions like mist and bat swarm.

Well truesight also makes Regulus' mines useless, at least in a surprise/trapping scenario.  You can now get the favor item which gives truesight as well as purchasing the Revelation Totem.

You can't wait him out - because he can simply chill there until Bat Swarm is up and so he comes out of Mist with full health and can swarm away - and all that time you're sitting there waiting for him other demigods are pushing on other fronts (depending on the map.)

The damage per second is not on the level of TB's Circle of Fire - but it is enough to kill creeps and to out-damage your regen on most of the lighter heroes.

My biggest argument against it is that he never has to retreat to heal.  There is an item which gives 5 seconds of invulnerability - but I played a game with Erebus where he would sit there for 20-30 seconds or more.  If your goal is to push and outpush the enemy as well as out-level them, Mist is for you.  More experience, war rank.

I'm not saying every Demigod should be able to buy a single item to counter an entire important branch in the skill tree, but there needs to be some counter for it.  Rock, Scissors, Paper and all that, you know?  Maybe the combination of truesight and another ability (an interrupt, purge, stun, etc.)  You don't want to make the ability useless, but you don't want to have no counter for it either.  Maybe it is something as simple as increasing the mana cost at higher levels...or making the cost a % of mana so that there is always a maximum duration, regardless of your ridiculous mana pool.

Freeze the cooldown while in mist form.  Nuff said.....  That'd fix the cheese and keep the ability viable.

I like a suggestion someone had about what to do with mist. The mist disables regeneration. Mana or health but probably not both. This adds a kind of limit to what you can do as far as hiding with mist to protect yourself from a near death situation, because they can camp you and there are limited ( but possible) escape options as your mana goes down constantly with your cooldowns.

Mist doesn't damage erebus anymore (it did in Beta 2). Bringing back the self damage as well as a mana cost would just remove its only viable use: avoiding damage (usually when close to death). With the DPS at 200, it would be reasonably useful against creeps, but still useless at damaging demigods, and so noone would use it (look at the complaints about ring of fire). Also, bringing back the self damage gives erebus a suicide option, and thus allows him to die without giving gold to the enemy; while that in itself would be fairly useful, a simpler option would be to give erebus a suicide button.

Suicide should be a code fix, the self damage keeps mist form balanced.  Instead of avoiding all damage you decide to take X damage instead of potentially greater damage.

If ooze did only aoe damage, I wouldn't use it. But since it slows down attack speed as well...

Anyway, the biggest issue with mist is taking the time to reset bat swarm CD (or any useful item) , imho. Though, playing an always escaping DG doesn't grant real tactical advantage. At least when playing in team versus.

I say give it a 1-minute length before it goes away, that way you can't just chill out in player's near-spawn areas and rack up damage, or just to be annoying.