Hearthpwn

This card needs a buff before the set it out to make it viable.
Let it do 2 damage to itself and lower it's max health from 8 to 6.
For a card that needs at least 1 other card to trigger it's benefit, it needs a much more impactful effect.

This card seem so bad but in big priest wild can be playable.. We ll see if it can be better then the actual version... In something can be better.. Against aggro having all those heals can be helpfull.. And would gave you time to summon your blood of ghun from deck and gaining board back and win. Very interesting card for sure.. Other then wild this is very very bad

 Combos nicely with Gift of Luminance. Topsy Turvy can also make the card have full health.

Some obnoxious combo will probably immediately appear in Wild.  Revive Priest reviving a few of these and then Circle of Healing Gift of the Naaru OTK garbage go

This card followed up by Desperate Prayer can be good but is very situational though.
Perhaps if you have Fan Club on the board it will be easier to trigger. 

All in all this card needs a lot of support to be valuable, which usually ends up not being good enough for top tier decks.

Overheal works only on itself do Desperate Prayer would do nothing. 

This deals 4 to itself and fan club heals only 3. So you would need something alse with it. This card seems bad

Oh my yeah you are absolutely right. Desperate Prayer will do nothing for this card. 
That only makes the card even worse then.

Depends, if overheal can only trigger once or multiple times per turn. And also if there will be enough viable heals in the future.

can be triggered more times I think

Absolute garbage unless there is some kind of OTK. 

Eternal Servitude once or twice

Divine Hymn Circle of Healing Gift of the Naaru multiple times