RTF is a global modification that replaces all towns in the game.

I was thinking of doing it this way, but a similar idea was used with Tier 6 – there, an alternative upgrade will be on the Assassin model, and Assassins have fur on their shoulders, so you could put something furry on their head; I wanted a bear head... but now I think a bone helmet made from a cat skull would be better.

The entire alternative upgrade will have skulls on the equipment; for Tier 1, there's a rodent skull, for Tier 2, bird skulls, and for Tier 5, lizard skulls.

There's no need to make it 1-to-1, nor to put a skull on their head (like with the Berserkers).
My suggestion was more about the idea of their weapon, and the rest of the equipment (armor) can be designed in many different ways.

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*The main problem with the Bonecrushers is that they are a "trash" unit even at the idea stage. They could be an acceptable Neutral unit, with such an "exotic" weapon, but not as a Tier 4 unit for the most armored Faction, where, in fact, all their allies will fight in an organized formation...

- Simply put, for a formation battle, the Bonecrushers look ridiculous, and this is the problem with their very idea. Ranged units? Yes! Berserkers with a large hammer, another two-handed weapon, or paired weapons (like axes) – that could be acceptable. But not gauntlets and daggers...

*In this regard, the Jaguars are much more convincing. Firstly, they are part of the Orc Faction, whose tactics are the opposite of the Dwarves. Secondly, they are larger, and their weapon allows for free hand movement, which allows them to grab/intercept the opponent's weapon, perform grapples, and use power moves. In Heroes 5, similar equipment is used by the Hunters, but since there are obviously no such units in your mod, my idea is to give the Orc Berserkers "Claws" or Blades attached to their bracers and similar devices. Instead of trying to give them a weapon "in their hands," which will obviously not go well with the animations of the Bonecrushers/Berserkers.

*However, these are just my suggestions and observations.