It happens regularly that I cast the big heal (right click) and perform a power attack (right click) at the same time. This only happens when I am under 20 mana and wait for it to regenerate. With 20 mana I can cast the big heal the mana is consumed to 0, my teammates are healed (i see the green numbers) but my paladin performs a melee power attack which can actually harm and kill people.
I only click once, I don't hold the right mouse button for too long so that the power attack starts after the heal. The power attack animation overwrites the heal animation. Two actions happening at the same time.

I assume you pressed the button twice though.
Anyway when you have not enough mana, you perform power attack on RMB click - it's expected.

regarding 20 mana dead - we'll investigate. Thanks for the report.

I don't know if it's cool that you do a default / power attack when out of mana. It looks so stupid, especially at fire witches

I agree with the point of loosing mana making you power attack. If I'm in the heat of healing and get manadrained then suddenly power attack throwing my weak paladin ass into the fray I usually end up dead.

It's not what he was talking about.

I finally recorded a video for this: https://dl.dropboxusercontent.com/u/960 ... attack.avi


I noticed how this behaviour works:
When you drop below 4 mana your character automatically switches to the attack. Why 4 mana? Because your small heal needs 4 mana.
When you have 4+ mana even after a big heal your heal skill stays active.
You have 30 mana, you press RMB, you cast big heal, you have 10 mana, heal skill stays actice.
You have 24 mana, you press RMB, you cast big heal, you have 4 mana, heal skill stays active.
You have 23 mana, you press RMB, you cast big heal, you have 3 mana, heal skill in the skill bar drops down (like being on cooldown or in this case not enough resources) and you automatically switch to the melee attack skill.
When you are between 4 and 20 mana and your heal skill remained active you can press RMB and it happens nothing, no melee attack. But when you once fell below 4 mana, doesn't matter if you got below 4 mana with small heals, big heals, mana drain bubble or whatever, you automatically switch to the attack skill.

In the video you see me perma casting big heals with a perma pressed RMB and I fall below 4 mana with the last big heal so I automatically switch to the attack. The animation of the big heal is cut off and the attack is executed.
This behaviour is too sensitive. In intense fights you cannot control if you click the RMB for 0.1 or 0.2 seconds and if you press it just a little too long you start the melee attack because the game recognizes and accepts the RMB click as soon as the mana is drained and not when the heal animation is finished completely.
Funnily enough, that you don't cast the next big heal that fast. You need to finish the heal animation to cast the next heal, but you don't need to finish the heal animation to perform a melee attack.


Edit:
I guess this behaviour with the cut off heal animation is caused by the forceswitch to the attackskill as soon as the mana is below 4.
There are several scenarios in which this behaviour is very annoying:
-You notice you are somehwere near but below 20 mana and want to perform a big heal so you already keep RMB pressed and wait until the mana is restored to directly cast the heal without delay. After casting the heal you drop to 0 mana and get forceswitched to the attackskill, cut off the heal animation and perform the power attack, because you can not release the RMB in time after you held it down waiting for the mana to restore.
-You have plenty of mana (let's say ~50-100) and cast some big heals with a perma pressed RMB. Then you recognize a mana drain bubble being thrown at you which drains your mana nearly instantly to "below 4", which forceswitches your active skill to the melee attack skill. If this would not cut off your heal animation you would have enough time to release the RMB to prevent the power attack. Since the animation is cut off you nearly always perform this annoying power attack when you got manadrained while healing.
- ...

Just wanted to bump this thread up again after one month of no response to the video. This behaviour is still present, happening very often and is very very very annoying.

If you cannot see what I'm talking about, play a paladin and rightclick heal when you have 20-23 mana. The heal animation is cut off at the very beginning when the character raises his arm and you perform a power attack.
I'm not talking about that it automatically switches to the attack when you are out of mana, that's ok. When you are not out of mana you have to wait until the heal animation is finished until you can perform any other action. But when you are out of mana after the heal the automatic switch interrupts the animation and this always leads to unintended power attacks.

If you still don't get my point or have trouble viewing the video linked in the previous post please tell me. This behaviour can not be intended and is really very annoying.

edit:
Now available on youtube if the dropbox .avi link is making trouble http://www.youtube.com/watch?v=FxNO-4d4NkE
and .zip for download, viewing at 50% speed makes it easier to see the behaviour https://dl.dropboxusercontent.com/u/960 ... attack.zip