Thanks to all and specially to Kyatric for help - but now i have another problem.
Normally the world/playfield have limits (size of the layout), so i created an playfield, that is infinitely!
The Player is always in the center of the screen and seems to move, but acuality the background/opponents/environment moves in opposite direction of Player. So the world seems to be endless!
(for my game it will work so)
But now i can't make a tail like in the examples mentioned.
("pin" with rope-style does not work)
HERE is an test-capx to see, what i mean with endless playfield.
(Control by touching)