The Shortening Rules Questions

[The Giant]

Is Xykon a Monster and/or a Player

Wandering Xykon is a Monster, not a player. He follows all the rules for Monsters except for those that relate to his movement and other unique capabilities.

That makes most of the next few answers obvious, but I'll go through them anyway:

Does Xykon trigger Explosive Runes

No. Only players can trigger Explosive Runes.

Does he take Damage from Explosive Runes

No. Only players take damage from Explosive Runes.

Is he a valid target for the Screw This card named Surprise!

Yes, because he is a Monster. Note that the part where the Monster is "saved as normal" means that you only get to save Xykon if you are taking his last Wound, because that is what is "normal" for Wandering Xykon.

Is he a valid Monster target

Yes. You can target him with anything that targets a Monster that does not specify "except Xykon" or is listed under the "Xykon Special" Monster ability.

Is he a valid Player target

No. You may not target him with anything that targets a player unless it also can target a Monster.

Can Durkon offer to heal Xykon
Can Xykon accept healing from Durkon

No. Durkon can only heal players.

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While Xykon is retreating towards the Safe Haven
Does he stop movement if he encounters a player

No. The new movement pattern of moving directly toward the Safe Haven replaces all of the previous movement directions for Xykon, including the one about stopping when he encounters a player.

Does he attack a player if his movement ends in a room with a player

Yes. Per the rules, "When Xykon ends his movement in a room with one or more players, he Attacks them."

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When using the variant rule No Turing Back and a player has lost his last wound

Do all wounds heal?

When does the above happen:
Immediately, when he drops half of his Loot?
Later, after he has missed a turn?

Yes; when they begin their next turn (after missing one), they start with a fresh set of Wounds.

On the skipped turn is he treated as being Paralyzed or Fleeing?

Fleeing.

Is he a valid target for PvP

No; treat the character as if they were fleeing the dungeon (except don't move them).

Is he a valid target for Xykon

No. Wandering Xykon will ignore them as if they were fleeing the dungeon.

Do all Shticks unflip?

No. You would need to rest in order to unflip shticks.

Do the effects of "Broken Weapon/Hysterical Aphasia/Turned into a Newt" end?

Hadn't thought about that, but sure, that's fair.

Does Durkon's Shtick The Hope of Returing Home end those effects

Yes and no. It unflips them, meaning that they can be used again, but it does not discard the Screw This! card. So if they become flipped again, they remain flipped. Although there's no reason you can't use Hope of Returning Home to unflip it again, indefinitely.