It would be nearly impossible to speak about Quantum Conundrum without bringing up Portal. Aside from a sharing a lead designer, both games draw from the same core ideas: first-person platforming puzzles bound together by a physics-defying device, a quirky atmosphere, and a persistent narrator who'll never find work as a motivational speaker. Solving the dimension-twisting problems of Quantum Conundrum was a lot of fun - in spite of how familiar many parts felt - but may have ascended from "great game" to "truly special", had it only found the means to expand just a little bit farther from its spiritual predecessor.
That being said, to call the game "a Portal clone" would be a disservice. Yes, you play as a scientific nobody forced to use a sciencey gadgetto solve various puzzles, but that's where the similarity in mechanics ends. In Quantum Conundrum, you're armed with something called the Interdimensional Shift Device (or IDS Device for short), a glove that gives you control over the world around you and, more specifically, the physical laws that govern it. This is done by pressing buttons on its surface to shift dimensions, a technique that adjusts the properties of everything around you in different and, often strange, new ways.
At first, you're hit with two easy-to-understand tweaks: the so-called Fluffy Dimension, and the less-cutely-named Heavy Dimension. Fluffy makes everything in the room weigh less, while the Heavy Dimension - you guessed it - packs on the pounds. Like most well-designed puzzle games, Quantum Conundrum focuses on teaching you core concepts, then adding to what you've mastered to raise the complexity. So, what may begin as "make this safe lighter so you can carry it" soon becomes "make this safe lighter to carry it to a pressure switch, then heavier in order to activate it" and so forth. Introducing more dimensions while gradually introducing new ways for them to interact maintains the rewarding feeling of solving a room, while curbing the frustration of what can, at first, seem an unsolvable puzzle.
The majority of these puzzles lie at the center of a larger objective: moving your character from A to B. Because of this, platforming sections (sometimes within the puzzles, and sometimes between them) are equally important to the experience. On the whole, these segments are somewhat more trying, as jumping across a field of various objects can be tricky from the first-person vantage. Balancing that annoyance is a fantastic checkpoint system that auto-saves your progress per individual hurdle rather than per total section. Generally speaking, navigating a series of speedy conveyor belts or jumping across a waterfall of slow-motion safes is just as rewarding an experience as figuring out how to rewire a door or deciding which object to place on what switch.