One lore card affects "Knights" units. Who are they ? Guards,Archers,Riders ?
Who are Knights?
You should check the Unit Reference Cards coming with the game: under the name of the unit, there are some keywords, being Knight one of these. Every unit whose Unit Reference Card reports the word "Knight" is selectable by cards affecting Knights
Currently, only the Citadel Guard units are "knights", for what it's worth.
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