察して is the te-form of 察する, and it is one of the verbs that take quotative-と. The meaning is "to notice/understand/guess (some fact, indirectly via a circumstantial evidence, a facial expression, etc)". The と-clause contains what is noticed/understood.
to notice they are chased (not by actually seeing the chaser but by seeing some indirect ...
This is about the difference in the speaker's perspectives. If you asked me, however, if the difference was huge (or very important), I would mostly have to reply negatively.
The former is told from one's （自分） own viewpoint.
"people that one/you get(s) along well with" or
"people that one/you is/...
This まで (no. 4) is what is being used here.
In English, this would be translated in most cases as "even". と just is quoting what is 言われる. Without context, therefore, I would translate your phrase roughly as:
The story of the gamer(s) (ゲーマーの話) (against whom)
people even go so far as (まで)
to say (言われる)
that winning is impossible (勝つことは不可能と)"
As far ...
When you see a father and a son together no one would ever say to the father "you look just like your son", but it would be perfectly natural to say "your son looks just like you".
In this example the father is the 'standard of comparison', so if you are going to use に it should be attached only to the father.
と treats both parties equally, so you can add ...
"Just so you know, ~~~."
The 「と」 here is a conjunctive particle used to form a light and casual kind of introduction before stating the main point.
Thus, 「言っておくと」 and 「言っておくけど」 mean fairly different things from each other in that the latter is used when you want to warn or caution the listener in advance about something that ...