1. What rank do I need to pass quests here? Answer
You need to have rank at least Crusader:
2. Can I pass quests with my friends here? Answer
It is only forbidden to play in a team of five players to pass quest.
3. Can I pass quests with non-ranked matches? Answer
No. You can't
4. I've won two matches and then I've lost one match but after that I've won match - is it enough to pass my three-victory quest? Answer
No. You need to have three victories in a row.
5. I've won two matches with quest heroes and then I've won with non-quest hero but after that I've won match with quest hero - is it enough to pass my three-victory quest? Answer
No. You need to have three victories in a row with quest heroes.
6. How do I pass quest with quest heroes? Answer
Each match won with one of three chosen heroes for quest.
For example you've got four-victory quest with heroes: Slark, Medusa and Pudge. You can win all these four matches for quest with Pudge or you can win first two matches with Medusa and second two matches with Slark.
7. I've completed my quest - can I start new quest? Answer
You can start new main quest only if the time of previous is expired
Thus, if you've created 12-hour quest, then you can create a new quest only after 12 hours.
An exception is the case when the previous passed quest was a PRO-quest.
The site's time: UTC + 3 time zone.
8. I don't understand how to use "Extended quest checking feature"? Answer
For example when you've won all needed matches for quest but then forgot about quest and started to play non-quest game - you wll have to use extended quest checking feature