Erratic Shield. A double layered shield with gaps surrounds the Experiment. For simplicity, use 6 panels for the shield that surrounds the Experiment, though a number of panels that equals a die size can work (my setup uses a d10 for 10 panels). Each Turn, roll 1d6 (for 6 panels) twice. Starting from the Northmost panel, the panels that match the results are the gaps where the Experiment can be targeted (and vice versa for the Experiment to target Heroes). On twin results, the shields stop rotating and stay open for the rest of the "Round" instead of rolling. Due to the concept of Rounds being used with this monster, it is recommended that once the players choose an order to go in, it should be maintained.

Reactor Pit The Experiment resides in the center of a cylindrical shield, and the floor of the area is 2 spaces lower than the platforms that the players walk on. The floor is also only one space wider than the Experiment, so any Creature that gets inside the shield will be in Melee of it. If Hook pulls the Hero beyond the edge of the shield cylinder, they take 1d6 Falling damage and are inside the shield with the Experiment. A Hero inside the shield is no longer blocked by the shield, and vice versa, so they are free to attack each other. While the Hero would get extra damage, any Hero that is isolated inside would be at a serious disadvantage by being the primary target of the Experiments attacks. However, if the Heroes all charge inside, the Experiment would use Hook to throw them back out, one at a time.