Tzn :
why you don't show r7 250X at higher graphics? paid to advertise only expensive products?
A selection of suitable cards have been tested at each resolution and detail setting.
The article is an illustration of game performance, not a detailed review of particular graphics cards or an advertisement for some cards.
An R7 250X will give you roughly 60% the performance of a GTX 760.
This would mean average frame rates for the R7 250X of roughly 35 FPS at "Medium Details @ 1080p" and 19 FPS at "Ultra Details @ 1080p".
This makes the card unplayable for "Ultra Details @ 1080p" and borderline for "Medium Details @ 1080p".
Typically a playable card will have minimum frame rate above 30.
These are my best guesses of minimum playable card based on other results:
For "Medium Details @ 1080p" an R7 260X or GTX 750 Ti are suitable.
For "Ultra Details @ 1080p" an R9 280X or GTX 770 are suitable.
For "Ultra Details @ 1440p" an R9 290X or GTX 970 are suitable.
For "Ultra Details @ 2160p", none of the tested configurations can meet minimum 30 FPS. With game and driver optimisations multi-card configurations will likely get there (2 x GTX 970 or 2 x R9 290X).