It's simple – your hero is like a drug addict, and for him, dungeons are unfamiliar territory; he reduces his movement speed if he doesn't know "pathfinding." But the Dark Elf Law grants him mastery over dungeons – it was necessary to at least get him out into the open air.
And also – if you have "War March," never rush to kill neutrals in an unknown location – in case of major trouble, they can be very helpful, extending the range of advancement by 30-40%.
Here /topic/7405/ I generally used "War March" as a perpetual motion machine for moving around the map (comment from 08.12.2012, 14:08, 3rd paragraph or from 08.22.2012, 18:26, penultimate paragraph).
As for the specific case, with Traveler's Boots, my hero would fall behind the Law by about 10% per turn. We ran along a circular route like this for two weeks – my main hero and the Law (sometimes we had to wait so that they wouldn't drift too far apart), and after each raid, the Red Bitch was hired in the undead castle and reappeared in the dungeon after two turns to participate in this fun.
Added after 42 seconds
By the way, what other undead castle is there?
Падение Грифона 136x136
Рельеф - 40%
Скрипты - 15%
Геймплей - 20%