When a webcomic updates but you don't want to make a huge deal out of it, what you do

[Menarker]

Quoted: "Slaying a Vampire: Reducing a vampire’s hit points to 0 or lower incapacitates it but doesn’t always destroy it (see the note on fast healing). However, certain attacks can slay vampires. Exposing any vampire to direct sunlight disorients it: It can take only a single move action or attack action and is destroyed utterly in the next round if it cannot escape. Similarly, immersing a vampire in running water robs it of one-third of its hit points each round until it is destroyed at the end of the third round of immersion. Driving a wooden stake through a vampire’s heart instantly slays the monster. However, it returns to life if the stake is removed, unless the body is destroyed. A popular tactic is to cut off the creature’s head and fill its mouth with holy wafers (or their equivalent). "

I assume you're referring to the Roy/Durkula fight that is ongoing as of this post. The previous vampire in story that snuffed it (Malack) was killed via dispelling his protection from sunlight while in the desert sun. In this winter-mountain setting, sunlight isn't readily available, but there ARE two viable sources...
A: Vaarsuvius is capable of casting the spell Sunbeam, which would pretty much do the same thing. He/She might not have it prepared right this day, but if they can keep him unconscious, V can ready it.
B: If Sunna, that High Cleric of the Sun God, could be persuaded that a defeated cleric means that their vote no longer holds any sway, then he would be a more ready source.
C: A few pages back, as we saw Belkar falling down the mountain, we can see a river below. A few rounds of being submersed there would do the trick as well.

This is all assuming that positive energy that brings it below the killing threshold doesn't do the job on its own (and they are in a cleric-heavy surrounding).

[Grandmaster_Skweeb]

Originally Posted by Aerozord

So I know, in D&D do vampires still die if you inflict enough damage to them or is there something extra you have to do? Like kill them with silver or cut off their head

Depends on the version, but typically they follow standard vampire tropes. Generally the vampire template comes with a slew of special abilities that make them very durable if approached without planning accordingly. They're kinda like liches in that they'll keep coming back until you deny them their contingency plans.

Most notably (for 3.5)

• armor class +6
• DR 10 / silver & magic
• heals 5hp each round if hp is greater than 1. When 0hp it assumes gaseous form until it finds its coffin home to regenerate. Cannot be hurt when in gas form.
• Swarm spells. Lots of swarms.

Weaknesses include:

• Sunlight. First round disorients. They get a single move or attack action, if neither allows it to escape it is outright destroyed.
• Complete destruction of the body. Disintegration spell is handy for that.
• Spark of Life. Removes undead immunities; makes for easier killing time.
• Immersion in running water reduces its hp by 1/3.
• Stake to the heart incapacitates said vampire but only for as long as the stake is in place.
• When resting in coffin it is extremely vulnerable (helpless status aka coup de grâce time) for the first hour until 1hp is restored, losing helpless status and standard 5hp a round kicks in.

[Flarecobra]

Well, considering this vampire can still heal himself via Inflict (level) Wounds on himself... On the other hand, if you recall... Roy's sword is particularly effective against undead.

[Menarker]

Too bad that Roy:
A: Hasn't mastered how to unleash that anti-undead effect at will.
B: Hasn't caught on to the fact that that vampire is being controlled by someone who isn't Durkon as opposed to it being his friend with a new mindset. This misunderstanding means that he may hesitate to use absolutely lethal force against him.

Back before Durkula's great reveal, Roy thought he could get his friend back by just ressing him right after killing him. That despite all of the eccentricities of vampire-Durkon, he was still Roy's good ol' pal.
But now, the notion that Durkon has taken a 180 in mindset is putting a damper on that.
If Roy thinks he is unable to convert Durkon back to the side of good (or is unable to learn that real-Durkon is being held hostage), then logically speaking, attempting to kill him and then raise him would be a stupid act since he'd be wasting the ressurection spells (and the diamonds needed to cast it) if Durkon was just going to go back to being evil again. Then he'll be cleric-less again and would have to recruit another. (Although being in a cleric-filled Godsmoot helps on that regards.)
Subconsciously, Roy may be holding back because of this (something that Durkula is counting on, which he has specifically stated).

[Flarecobra]

I don't think that's something that can naturally be controlled though. Especally since the effect has showed up when he wasn't even fighting undead.

[Aerozord]

are we supposed to know why that forcefield is there in order of the stick?

[Terex4]

It was explained in a forum post.

The barrier is a normal part of the Godsmoot. It's the answer to the question that was voiced repeatedly around these parts, "Why doesn't one of the high priests just step out of the room and nullify the vote?" but I can't fit everything in every comic, so we haven't seen it until now.

I thought its origin would be somewhat self-evident given that I made it the same exact color as the Northern Gods' energy auras, but I guess not.

[Aerozord]

I'd say that was a poor explanation because of two reasons. First if its normal why is everyone unaware of it, secondly they clearly had a plan for what they'd do if there was a tie and yet standard set up for this prevents that plan from even occurring.

[Ryanderman]

Originally Posted by Aerozord

I'd say that was a poor explanation because of two reasons. First if its normal why is everyone unaware of it, secondly they clearly had a plan for what they'd do if there was a tie and yet standard set up for this prevents that plan from even occurring.

I think everyone is aware of the force field. As one of the priests said, all they had to do was go to the top of the stairs and call for an usher. That is exactly what Balder's priest is doing; the problem is Durkula killed all the ushers.

[Gregness]

I'm really digging the new sidekick in Kill Six Billion Demons. She knows tropes.