I’m trying to work out if there is a way of evoking the sort of thing Vengeance for Calth aims for in a way that is actually a good addition to the game. ‘My specific subfaction hates this specific subfaction so here is a new ability they can use’ is the straightforward way of doing it, but rarely relevant, and even when it is may not be used, given the CP cost and that it only applies to one unit. So although it does what it was designed to do, I’d say it was poor design.
Perhaps something like this would be better:
So each phase you get to reuse one stratagem if you’re facing a favoured enemy. No additional effects to remember, just do more of what you were doing already. Represents your units fighting slightly harder against a hated foe. Possibly broken if there are stratagems that are really good if you can use them twice, but could control for that by specifying which stratagems can be used in this way.Vengeance for Calth - 0cp
If your opponent’s warlord is a Wordbearer, you may immediately use a stratagem a second time this phase. You still pay the CP cost for that stratagem.