Gehanna

Character is kind of like a Native American.
Need something that relates to wind.
The land is flat with no mountains.
Necklace is worn at all times.
Story is fantasy based.
The necklace is given to the main character.

With the above points in mind here is my recommendation:

As opposed to a necklace created from a mythical creature, how about a necklace weaved from the hairs of an ancient. Could be a powerful shaman who has passed on or some significant elder. The necklace could be weaved from the hairs of his or her head and passed down to your character.

Hunters, especially bow hunters, will often take the hairs of some animal (the beard of a turkey) or even human hair and tie them to their bow/weapon. This helps them determine wind direction.

This character of yours living in the environment he is in could go so far as to pull some hairs from the weaved necklace and use them as a navigational aid considering the absence of landmarks such as mountains and etc.

As far as the name of the horse, if you want a name synonymous with calling up of the dead or of evil spirits then use of the term Seance may not be appropriate. What you speak of refers more to the abilities of a Necromancer and conjuring or invocation. A seance is limited in its purpose and intended only as a means of communication with those who have passed on (usually relatives or loved ones). These spirits are not evil and are not summoned for any purpose other than communication.

I don't mean to come across as if I am trying to tell you what to do. These are just some suggestions from a novice you may or may not wish to consider.

Sincerely,
Gehanna

valeca

Y'know, this was a rather important detail Might have been more helpful the first time around, hmm? Especially after telling us about not wanting to lose it in the storm on a mountain

There are some good idea's here. You can probably make the rest up yourself now

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Verago

What about a hollow bone necklace that can be blown and makes a cool, vibrating sound.

Ajax

How about a cool looking fossil rock like a trilobyte or something like that?

What about amber or hematite or opal?

Maybe it's the arrowhead that killed his father, and he keeps it on a necklace?

I have no idea if Native American's wore these kinds of things, so you'd have to research them first.

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