Imagine Software, 1983
Jumping Jack knows a rhyme, a four verse limerick. Unfortunately he is unwilling to recite it unless you help him scale the levels to the top of the screen. Only by helping him through all twenty screens will you learn the entire rhyme. For each screen completed he will tell you two lines.
Jack is faced with eight layers initially containing only two moving gaps, the gap moving leftwards travels upwards whilst the gap moving to the right travels downwards.
Jack must jump through the gaps above him whilst avoiding falling through the gaps below.
Jack can only move upwards by jumping through the gap above but he can also move left and right. Should he run off the edge of the screen he will wrap around to the other edge. Should he fall down a layer he will bang his head and remain unconscious for a period of time during which he cannot move. Every time he arrives at the bottom of the screen unconscious he loses a life.
At each successful jump a new gap appears at random - the first three new gaps descend then the next three ascend - up to a maximum of eight gaps. On making a successful jump at the top layer the 'next level' sequence is entered, and the next part of the rhyme is given.
Hazards will begin to appear after the first level - one initially, then two right up to a maximum of twenty, one for each level completed. They all ascend and if Jack collides with a hazard he will be knocked unconscious.