[cgmv123]

Cases 1 and 2 are not valid climbs because of non-sequential contact and contacting more than 3 zones.

Case 3 is a valid climb* because there is no non-sequential contact and only 2 levels are contacted.

Case 4 is a valid climb* because there is no upper bound to Level 3.

Case 5 is a valid climb* to level 0 because the floor was never left. If the robot were to break contact with the floor, it would be a valid climb* to level 1.

Cases 6 and 7 are valid climbs* because there is no non-sequential contact and only 2 levels are contacted at a time.

Case 8 is a valid climb* like Case 3.

Case 9 is a valid climb* like Case 4.

*assuming the robot reached that position with a valid climb.

Also note that illegal and invalid climbs are 2 different things. It's legal to climb the Pyramid in an invalid manner, it just doesn't count for points.