Can I suggest evil creature (character is evil too) to serve as a guard for the rest of dungeon?
The creature was last standing after battle, and I promissed to save his life after our quest is done.
Would you allow it? Is it reasonable enough (he will be obviously dead if refused)?
You're not asking for rules, you're asking for advice. Expect massive table variation. Flagged to be moved to advice.
As far as the situation goes, I don't have enough information. Evil is too vague to make a call.
We were fighting with demonic vermins, they are intellectual.
There were 5 demonic scorpions, and we killed 4 of them. Than wounded the last one.
And than, on my character's turn, I casted suggestion: "Maybe, you'll serve as guard for me for a wile? After we escape the dungeon - I'll save your life and you will be free to go, if no - we will kill you".
And it failed a will save.
For me - it's truely reasonable. But is it obviously harmful?
Expect table variation. There are no black and white rules for this scenario. What is reasonable/harmful will vary from person to person.
I'm talking about "harmful" vs "absolutely harmful" :)
Table variance.
Following you and assisting you isn't "obviously harmful" so yes, you can suggest it to guard you for the duration of the spell, provided he fails his save. However, if he should come into an "obviously harmful" situation, such as another combat where following the suggestion would put it in danger, the spell will automatically fail and he would probably be a little angry.
Asking something harmful automatically fails the spell, not "entering the dangerous situation", isnt it? Like be suggested to bring an apple to a guard and being attacked by a criminal in the middle of the journey will not negate the suggestion.
And he needs to know the risk, if it really lives in this dungeon and knows that it's dangerous. But if it will serve as guard he WILL NOT DIE INSTANTLY, he has a chanse to live. Serving as guard can be harmful, but can be not, but it is obiously better than die instantly.
Do you have a RAW link that spell ENDS if he enters harmful condition by suggestion?
Asking the creature to do some obviously harmful act automatically negates the effect of the spell.
So, you are right that any danger that comes after the suggestion was made wouldn't cancel the spell. However, I would say that specifically guarding you and your party would obviously bring harm to him should you be attacked, and therefore wouldn't work as a suggestion.
Obvious danger does not mean that he will die instantly, rather that if he follows the suggestion, there is a significant chance of some harm befalling him.
So, you think, no mind controlling on low levels, ha? :)
I can just suggest him to listen my arguments and talk about my leadership skills, and then roll my INCREDIBLE CIPLOMACY to ask him to be my guard (charisma check vs vermin) :) But it will be sooo... stupid?
If he is truly a non-intelligent vermin, then this whole thing is pointless as he is immune to mind-affecting effects. If he isn't mindless though, just talking to him directly and convincing him to join you is actually a pretty good idea.