Because there are no advanced or professional tutorials for slots games, roulette, poker, black jack, etc. For online casinos ?.
Someone could give you some idea, how to make a good slot game ?.
Several lines of game, animations, bonus, jackpot, connection to database, php, mysql, etc.
I am a graphic designer, and it is very easy for me to contribute good sounds, videos and graphics.
But I need a real guide how to make a professional video slot, like this example: youtube.com/watch
Would anyone agree to form a team with me, and share resources, ideas and projects?