I'll make this short.
For monster IDs 1113 and 1572, "Drops", the current GIF animation is:
(http://file5.ratemyserver.net/mobs/1113.gif)
This looks much more like a slow-motion walking Drops than a standing Drops. Based on a same-family monster, the Poring, whose animation is:
(http://file5.ratemyserver.net/mobs/1002.gif)
It's quite different. But in-game, their standing animation looks the same. The Drops animation should therefore be replaced by this one (without the white background):
(http://midgard-library.org/images/monstres/1113.gif)
It's quite a small detail, but I still think it should be corrected.
EDIT:
There's also a speed issue with Marin. It is:
(http://file5.ratemyserver.net/mobs/1242.gif)
It should be:
(http://midgard-library.org/images/monstres/1242.gif)
EDIT2:
Speed issue with Ghostring as well. It is:
(http://file5.ratemyserver.net/mobs/1120.gif)
It should be:
(http://midgard-library.org/images/monstres/1120.gif)
EDIT3:
Speed issue with Angeling as well. It is:
(http://file5.ratemyserver.net/mobs/1096.gif)
It should be:
(http://midgard-library.org/images/monstres/1096.gif)
Same thing with Archangeling. It is:
(http://file5.ratemyserver.net/mobs/1388.gif)
It should be:
(http://midgard-library.org/images/monstres/1388.gif)
I am sure not all the mob gif will match the in-game animation. I could only say the person that does them isn't perfect in those cases.
Actually, I do allow some degree of difference. As long as the reader can tell this is the monster they see in game I think it's okay.
Even when generating some of the newer monster's gif. I sometimes purposely remove the effects/frames of some mobs to save space/bandwidth. For example if you haven't notice the gif of Satan Morroc, Nidhoggr's Shadow and Gopinich were all different from their in game movement. I think in-game they have some smoke around them while they move. I removed them so they don't stretch out the mob window too much and it help the page load faster with less frames.