This is 4DTetra(Polytope5) version of my 4DRubikCube. The mechanism of this puzzle is different from 4DRubikCube. This is rather similar to that of my "ArrowTetra".
This is made up of 1 HyperPyramid(4DPolytope5). This hyperpyramid is made up of 5 pyramids. And each pyramid is devided to 4 small pyramids. There are 5x4=20 small pyramids in all.
View window is devided to 5 small view. Each view has different eye point. In each view 1 pyramid is not visible, because it is contaminated to all other pyramids. So it is impossible to draw that pyramid. Each pyramids are discreminated by color.

[How To Use]
You can rotate whole pyramid by mousedown outside large pyramid and drag.
You can rotate each small pyramids by mouse down on each small view window.
You can rotate pyramids in 2 mode.
In each case 4 small pyramids will rotate and exchange location.

(1) If mousedown on the side of large pyramid and mouse up on the same side of large pyramid, then that large pyramid(made up of 4) will rotate.
(2) If mouse down on the top side of large pyramid and mouse up at another large pyramid, then small pyramid of top of each large one rotate and exchange each small pyramid. In this case the hidden 5th pyramid also will rotate and exchange small pyramid. And 3rd small pyramid will disappear to hidden space.

In the case of (2),4 pyramids rotate to following order. P1(mousedown)->P2(mouseup)->P3(next piramid)->P4(hidden pyramid->P1. P3 disapper and P4 appear to the location of P1.
If you want to return to the previous state, you must mousedown P3 and mouseup P2. If you mousedown P2 and mouseup P1, the pyramids does not return to the previous place.