Attempt to add new spells and skills.

Gerter, in the video example, are you activating the Berserker's Rage spell on the zombies or...?

No, there's just a script that uses UnitMoveAttack().

I checked the spell that psatkha provided, and yes, it can be cast, but there's no effect. On the other hand, such "empty" spells would be very useful for adding cool effects to battles without affecting the course of the battle. As expected, the xdb files don't contain much besides basic information; all the mechanics are inside the exe file. It definitely won't be possible to implement a new combat spell mechanic (using scripts). If it's designated as a "travel" spell, maybe it's possible, but in reality, new travel spells won't be very useful.