This page is just a reference of all the known Steam APIs, I do not know how they work. Please do not email me with questions.
UNDOCUMENTEDGetLiveLeagueGames
https://api.steampowered.com/IDOTA2Match_247040/GetLiveLeagueGames/v1/
UNDOCUMENTEDGetMatchDetails
https://api.steampowered.com/IDOTA2Match_247040/GetMatchDetails/v1/
UNDOCUMENTEDGetMatchHistory
https://api.steampowered.com/IDOTA2Match_247040/GetMatchHistory/v1/
UNDOCUMENTEDGetMatchHistoryBySequenceNum
https://api.steampowered.com/IDOTA2Match_247040/GetMatchHistoryBySequenceNum/v1/
UNDOCUMENTEDGetTeamInfoByTeamID
https://api.steampowered.com/IDOTA2Match_247040/GetTeamInfoByTeamID/v1/
UNDOCUMENTEDGetTopLiveEventGame
https://api.steampowered.com/IDOTA2Match_247040/GetTopLiveEventGame/v1/
UNDOCUMENTEDGetTopLiveGame
https://api.steampowered.com/IDOTA2Match_247040/GetTopLiveGame/v1/
UNDOCUMENTEDGetTopWeekendTourneyGames
https://api.steampowered.com/IDOTA2Match_247040/GetTopWeekendTourneyGames/v1/
UNDOCUMENTEDGetTournamentPlayerStats
https://api.steampowered.com/IDOTA2Match_247040/GetTournamentPlayerStats/v1/