What is the limiting number of challenging some one per day or per week

Answer 1

570 from a user's pov:
one-to-one: a limit of 15 challenges for a time frame of 24 hours. after 24 hours passed from opening a challenge a new one can be opened and so on.
one-to-many: a limit of 40 challenges in a time frame of about an hour. after an hour passes a new challenge can be opened by the user. the limit from one-to-one applies.
at receiving there isn't a limit.
there is a visibility limit, as not all challenges will be visible if you have a total of over 150 (don't know the exact number) in the play tab

Answer 2

as much as you can, they is no limit, recently someone gat the highest 2in in a day, which is 754 wins, no limit just keep on playing

Answer 3

As you can

Answer 4

Per person in one day it maybe 10 or 12