- A reference guide and manual in Russian for Heroes 3.

- 2.42 (SoD Light) xlsx: https://yadi.sk/i/Aq4PYEns3GDFkH [6 MB]
It doesn't open in Office 2k with a converter, it says "too many different cells," so your fancy Office probably can't handle it any other way. And PDF is not a great format for a reference guide; its purpose is to standardize printing. Especially without navigation.
In general, IMHO, the new version is overloaded with all sorts of additions. The original was less than 80 pages, and I use almost a dozen of them:

Hero skills, troops, and specialization at the start
Hero specialization. Spells
Probability of a hero receiving a specific skill
Relationship between hero level and the number of experience points (XP)
Spells used in HMM III
Probability of spells appearing in the city's magic guild
Market. Exchange rate
Artifacts, their types, and properties. Animation of composite artifacts
Logistics. Features of movement on the map
Objects on the map that allow you to obtain resources
Monsters in the game and their features
Calculation of damage dealt in combat

In Excel, their links can be moved to the main page; in PDF, it takes time to find them in a multi-page table of contents.
This doesn't mean that the rest is unnecessary, but it's about speed and convenience.
- I found an old error/typo in the physics guide:

Dirt Road – increases speed by 25% (actually – reduces MP consumption by 25%);
Gravel Road – by 35%;
Cobblestone Road – by 50%.

Someone doesn't know how to calculate percentages;)

Added after 22 hours 33 minutes
I suggest writing here how long it takes to open the 2.x physics guide on your machines, and with what program, on what hardware. For example, an early version of Foxit Reader is very fast but also very buggy, and Adobe itself weighs as much as an operating system.
On my "typewriter" (by the standards of 2012, when it was assembled) - G3220, 8GB, HDD, office2k, without swap - the old physics guide 1.4 opens in one and a half seconds, and that's quite a lot. I'm afraid to even imagine what will happen with the new physics guide and Office; no timer will be enough.