Bug type: Non-KMS maps don't function properly.
Brief bug summary: Maps that don't exist in the Korean version of MapleStory lack features.
More details:
1. Familiars don't affect mesos/drop rates in maps that aren't in the Korean version of MapleStory.
Example of familiars: Big Spider (50% drop rate), Eye of Time (% mesos rate), Wolf Underling (80%? drop rate)
Example of maps: Mori Ranmaru's drops aren't affected by familiars, as he doesn't exist in Korean MapleStory.
However, drop buffs such as Holy Symbol (Bishop), Lucky Winter, drop coupons or 2x events affect drop rate there.
2. Maps that aren't in Korean MapleStory don't get affected by level reduction.
You get the same amount of mesos for kiling a Blackgate City mob at whatever level are you (180, 220, 240). Maps that are in Korean MapleStory though get reduction for being about 20 or more levels higher than the mobs.
Quests that need you to kill "mobs near your level range" also count as long as the mobs don't exist in Korean MapleStory. For example, a level 250 player can finishg such quests by killing in Mysterious Path 3 or Northern Heights (popular mesos farming maps in Reboot world).
3. Elite monsters/bosses won't spawn in maps that don't exist in Korean MapleStory.
4. Runes will not spawn in maps that don't exist in Korean MapleStory.
Edit: Might be a bit off. Refer to AKradian's comment for additional information!
http://forums.maplestory.nexon.net/discussion/comment/36114/#Comment_36114
There might be more that I missed out.
Steps to reproduce: Kill monsters in a map that doesn't exist in the Korean version of MapleStory. Example: Wolf Spider Cavern in the Big Ben of New Leaf City.
Character name: Irrelevant. This isn't a character specific issue.
Character level: Irrelevant. Level doesn't matter.
Character job: Irrelevant. Happens to every class/job.
World name: Irrelevant. Happens in every world, in both Europe and North America.
Date and time of the incident: Irrelevant. It's been like that for years.
Comments
Drop buffs in general seem to be glitching a lot recently (http://forums.maplestory.nexon.net/discussion/10654/drop-gear-not-working), and as you can see people are complaining about Arcane River maps, which are in KMS.
2. Regarding the meso drop penalty: you're right.
Regarding the "mobs your level" for quests - all mobs over 150 count if you're over 150. This is true for KMS maps as well (such as Temple of Time maps). MP3 mobs are over 150. Northern Heights mobs don't count for "kill mobs in your level range" if you're over 150 (just tested it with a level 204 character. The mobs there didn't count either for attendance or for "The Sengoku'ing").
3. Correct about elite mobs and bosses.
4. Runes do spawn, but some of them (most notably Rune of Darkness) don't perform their function, just give the exp buff.
Note that Rune spawning rules have changed recently, and runes will only spawn if you're within strict level range of the mobs (-10 to +20 levels, I think). The "150+" rule does not apply. So if you're 200 and farming at MP3 (non-KMS) or Road to Oblivion (KMS), the mobs will count for "level range" quests, but you will not be able to spawn runes in either map.
Just yesterday as I was trying to get kills for the attendance event; I'm level 200, Detour to Oblivion didn't work (may be due to being a starforce map..? didn't try RTO) but MP3 did.
Thanks for the other information!
I don't know why Detour to Oblivion didn't work for you. It's working for my 204 character right now.
Don't forget that there are SO MANY recipes and you might be just having good luck.
Try going on a place like Yu Garden and get a big sample size with and without Big Spider.
Having good luck every time I bring the Spider out? Hmmm.....
What, exactly, are you counting at Yu Garden, and how?
Horse/kettle/incense burner drops from the sheeps, I farmed there for two hour and got 19 total (combined) without big spider and 21
Rare drops are way too subject to the crappy Maple RNG's moods. I remember many many years ago, pre-BB even, before any familiars, you could get anywhere between 0 and 10 Pieces of Time in an hour of farming at Road to Oblivion 4, depending on whether you managed to find the "lucky channel".
Try counting something more common, like valentine's boxes.
And that's besides the fact that drop buffs in general might be glitchy currently, as seen in the link I posted in my first response.
> Try counting something more common, like valentine's boxes.
I think familiars might just actually affect drop rate for items that exist in KMS and that's it though? I didn't confirm it but it's a possibility
I don't see why they would? Strictly speaking even if drop rate were programmed as such, it would be the reverse as familiars don't exist in KMS.