Cyclops Valley - This is the easiest one. No spawn nearby, good ledges for taming, small spawn area. Note: you can walk to this location using the teleporter to the south. Oasis - Mare tends to spawn on SE side of pond, a few ledges, some aggressive spawn. Two Bridges - Large spawn area, few aggressive critters, many ledges. There are additional spawns in Wind Park (far north end of Wind) and in the Terathon Keep (tough to get to and tough to tame). Each of these spots spawns a nightmare about once per day. The spawn can occur at any time. The spawns are not linked; a spawn in one location doesn't preclude a spawn in another spot. There is no "spawn blocking"; riding a tamed mare will have no effect on the spawning.
(Von): Nightmare spawns..: 1.terakeep last spawn was 742am e.s.t. 2. cyclopse valley 1030am e.s.t.(28 hoursafter the last) 3. unknownprobableyafter 10am e.st. 4.oasis unknown. probabley after 10 am e.s.t. same with Wind and 2 bridges
Thanks for this I have a question for the GMs though... what is the rationale for limiting the mare spawns to 20-29 hours per? All this really ensures is pretty much the same group of people getting hold of the mares and selling them for profit. Dragons and WW's spawn at normal rates, so why not mares?
If you're interested in an answer from a GM, I'd suggest pming them for the highest chance of a response or at bare minimum, tagging one of them. They only frequent certain threads so often and ignore certain threads that have questions that may have been answered in the past. Maybe even ask the question in IRC whenever you see Telemon discussing things and ambush him with the question.
Pics load fine for me. Might be an issue with international CDNs or something. I've reproduced them at this imgur album for you: https://imgur.com/a/UXvmOPT