Depending on the story and dramatic appropriateness, someone may go for a spectacular decapitation, although probably with a saving throw to avoid it. Alternatively, it can be a save for damage (which is more along the lines of 5th edition's stance on save-or-die effects).
Now, if you're talking about no combat, but rather someone willfully sticking an appendage in there (or an unconscious person moved half in, or something), then I'd say it's a more clear cut situation (see what I did there? :p )
Of course, there's always the chance that the DM rules that the gate closes and ejects the target one side or the other (usually the side that has more body), to prevent a munchkin group from weaponizing "Arcane Guillotine via Closing Gates".
It's clear that the spell is not meant to be used that way. If so, it would state that's what happens whenever a gate closes. That said, I guess it's entirely up to the dm and the situation. For instance, if my players were in a situation where they have to get rid of something that's attached to them (like a parasite or heck, a stick of dynamite) I think I would let it fly. Perhaps I'd even go so far to add the word "willing" to creature so that the spell can't be abused for this unless you have a special situation.
Otherwise, if you'd wish to use it offensively I'd make the character/monster make a saving throw, probably Dexterity, in order to avoid full damage, dc depending on how much of their body is through the portal.
I would never try to stifle a player trying to do something interesting, but I wouldn't make this easy. At the very least, I'd give the enemy a save, and have this effect end the spell. I wouldn't expect this sort of effect to kill the enemy either, unless they were already in a situation where they couldn't try to evade, ie. an unconscious or paralyzed enemy. TO reject the situation entirely, a DM could argue that a portal works on either the whole body, or none at all, ie. you move through the portal as soon as you touch it.
So i was wondering, if you cast arcane gate, place a creature's head in the portal, and close it, will it decapitate it?
Fringe cases like this are always up to the DM.
Depending on the story and dramatic appropriateness, someone may go for a spectacular decapitation, although probably with a saving throw to avoid it. Alternatively, it can be a save for damage (which is more along the lines of 5th edition's stance on save-or-die effects).
Now, if you're talking about no combat, but rather someone willfully sticking an appendage in there (or an unconscious person moved half in, or something), then I'd say it's a more clear cut situation (see what I did there? :p )
Of course, there's always the chance that the DM rules that the gate closes and ejects the target one side or the other (usually the side that has more body), to prevent a munchkin group from weaponizing "Arcane Guillotine via Closing Gates".
At my table, if you do it once, you're a bad ass and everyone's going to cheer. Do it more than once and you risk becoming "that guy"
"Not all those who wander are lost"
It's clear that the spell is not meant to be used that way. If so, it would state that's what happens whenever a gate closes. That said, I guess it's entirely up to the dm and the situation. For instance, if my players were in a situation where they have to get rid of something that's attached to them (like a parasite or heck, a stick of dynamite) I think I would let it fly. Perhaps I'd even go so far to add the word "willing" to creature so that the spell can't be abused for this unless you have a special situation.
Otherwise, if you'd wish to use it offensively I'd make the character/monster make a saving throw, probably Dexterity, in order to avoid full damage, dc depending on how much of their body is through the portal.
Subclass: Dwarven Defender - Dragonborn Paragon
Feats: Artificer Apprentice
Monsters: Sheep - Spellbreaker Warforged Titan
Magic Items: Whipier - Ring of Secret Storage - Collar of the Guardian
Monster template: Skeletal Creature
I would never try to stifle a player trying to do something interesting, but I wouldn't make this easy. At the very least, I'd give the enemy a save, and have this effect end the spell. I wouldn't expect this sort of effect to kill the enemy either, unless they were already in a situation where they couldn't try to evade, ie. an unconscious or paralyzed enemy. TO reject the situation entirely, a DM could argue that a portal works on either the whole body, or none at all, ie. you move through the portal as soon as you touch it.
Yeah, I think this is how I would rule it too. However, the spell describes that this is not truly the case. I mean:
Any creature or object entering the portal exits from the other portal as if the two were adjacent to each other;
If you were sucked through, this sentence is either nonsense or obsolete.
Subclass: Dwarven Defender - Dragonborn Paragon
Feats: Artificer Apprentice
Monsters: Sheep - Spellbreaker Warforged Titan
Magic Items: Whipier - Ring of Secret Storage - Collar of the Guardian
Monster template: Skeletal Creature