Hearthpwn

Give a medal to Darlequin

Aren't all these cards using overkill to described an effect dealing with 'excess damage' overkill (ha)...? Imagen if explosive runes read : overkill: deal excess damag to the enemy hero. 

Just let the card read "[...] for any excess damage dealt by this".

The idea about overkill is that something ook interesting can happen if there is any excess damage!

Honestly, a day after I posted Draining Imp, I thought that the heal should either go back into Draining Imp or go to both minion and player, because as it is, it’s crappy Lifesteal.

So that if Draining Imp trades with a 1/2, it currently heals Warlock for 1. Healing itself would make for a non-impact trade, and healing itself and Warlock would be all right in my opinion.

but I felt that was to much of an edit.

Abandon ship is quite interesting :)

Excessive Violence is a great concept for a card and I think Hearthstone needs more cards like this one:  powerful effects with a big downsides. I would compared this card to the effect of Coldlight Oracle, because you can surprise greedy control decks if the overkill activates and maybe burn their win condition.(why not use both!?) Best case scenario: the overkill does not trigger and dealing 5 damage for 2 mana is absolutely insane!

Excessive Violence, for the picture alone.

My stupid opinion
Shadow Mend - nice card, reminds me of Light of Naaru, looks pretty balanced when you only have one way to make heals do damage.
Twist of Fate - bonkers. Free superheal for just 10 mana and 2 cards would make it autoinclude in every semi-control archetypes. A solid NO for this one.
Alleria of the Void - for one thing wording is really weird. It makes things like shudderwock stack AoE damage to absurd levels. For second, giving 3 dmg hero power for just 5 mana is absolute nuts. This hero should cost 9 at the very least.
Dreadlord Jaina - Demons with lifesteal is again stupidly overpowered. And giving warlock free 6/6 infernals won't make it any better.
Extortionist's Blade - seems nice on paper but can lead to absurd tempo gains when combined with any weapon buffs. 4 mana cost would fit better.
Draining Imp - looks like a pack filler.
Excessive Violence - unusable by rogue, 1 damage more than eviscerate with this possible downside makes it almost completely unplayable
Unsafe Battlemace - in this condition it almost always will be outshadowed by Gorehowl, pretty useless thing to have.
Elusive Rogue - a card with cool design, but it shouldn't have keyword Overkill, something like "Deathrattle: if this minion has less than 0 hp return it to your hand" would be better.
Abandon Ship! - a card that kills a minion and pretty much destroys 2 adjacent ones has insane value in any situation. Too powerful.
Overcharged bolt - another pack filler but with a fun value of three 'over' in text.
Rowdy Fan - pack filler.
Purging Flame - Wouldn't be better to just say "Overkill: Silence this minion"?
Bloodthirsty Chicken - a meme
Inspiring Champion - pretty useless unless you somehow make this live for a turn protected by taunts or something. I can't see a situation where this card will be better than Goldshire Footman.
Gonk's Chosen - great concept and pretty good balance. Really interesting card, I like it.
Bloodthirsty Jungle Chicken - a better meme. This one can even be usable in buff decks.
Gutspiller - Kinda uninspired. Nothing to say about this one.
Wardruid Loti - this is insane. Druid historically has hard times dealing with wide boards. Giving them ability to wipe 7 minions with just this + Bite should never be in the game.
Overkrill - meme that can actually be pretty viable in some buff decks cuz you summon a copy with all buffs on it.

Chicken all the way!

Purging Flame for me. Also like Twist of Fate.

Two absolute favorites for me.

Shadow Mend is just perfect. Playing with the Healing and Shadow Side of the Priest is done really nice.

And Excessive Violence. I love the design and the idea behind that.

Shadowmend is very cool, I really like how it has the flexibility and theme of priest with healing or damage. But very good competition!

Omg Bloodthirsty Chicken are invading us, OMG OMG!

But dreadlord Jaina hasn't got overkill? I like gonks chosen the most

The Overkill is located on Jaina's Hero Power; you can see it at the bottom of the Poll's home post.