The journey from the 3x3 to the 4x4 Rubik's Cube can be daunting. With its added complexity, the 4x4, also known as Rubik's Revenge, presents new challenges. However, with patience and a clear approach, you can easily learn how to solve it! Let's dive into learning how to solve the 4x4 Rubik's Cube.
Introduction to the 4x4
Unlike the 3x3 cube, the 4x4 doesn't have fixed centers. This means orientation matters even for the centerpieces. It also introduces the possibility of parity errors, which are situations where only one or two pieces are out of place, which does not happen in normal 3x3 cubes.
The Reduction Method
The most widely used technique to solve the 4x4 Rubik’s Cube is the 'Reduction Method', which breaks down the puzzle into manageable steps. The ultimate goal here is to make the 4x4 behave like a 3x3 so that we can apply familiar strategies.
Step 1 - Solving the Centers
Start with any color, let’s choose white. Move the 4 center pieces around so that you form a 2x2 block of white on one side. This part is pretty intuitive, you just have to make two 2x1 blocks and pair them together! Move on to the opposite side after that, which is yellow in this case. Solve the yellow centers the same way you solved the white ones while keeping the white ones intact using insertion techniques. After solving the 2 opposite centers, we have to solve the 4 remaining centers using intuitive techniques and the same insertion techniques used to solve the yellow side. Make sure you solve the centers following the 3x3 color scheme, which goes like this: White on top, with green, orange, blue, and red in clockwise order.
Step 2 - Pairing Up Edges
This can be tricky. The goal is to get two identical edge pieces next to each other.
Find two identical edge pieces and get them on the horizontal layer of your cube. One should be on the top side of the layer and the other on the bottom. Pair them up using Uw and Uw’.
Ensure you keep previously paired edges.
Store paired edges at the U or D layer to avoid disrupting them as you pair up other edges. After you fill up both the U and D layers, you’ll be left with 4 remaining edges. Solve them by using the flipping algorithm which goes like this - R U R' F R' F' R. The trick is to put both edge pairs on either the top or bottom side of the horizontal layer, do a slice (Uw, Uw’), perform the flipping algorithm, then reverse the slice (Uw’, Uw)
By the end of this phase, the 4x4 should start looking like a scrambled 3x3.
Step 3 - Solve Like a 3x3
With the centers formed and edges paired, the cube can be solved like a regular 3x3. Use algorithms and methods you'd employ for the smaller cube, solving it layer by layer.
Step 4 - Addressing Parity Errors
Parity errors are unique situations in the 4x4 where something seems "off". For instance, you might have just one edge flipped or two edges swapped. This can't happen in a 3x3, but in a 4x4, it's a result of the cube’s inner mechanics.
There are two common parity errors:
- OLL Flip Parity: One edge appears flipped. The technique for solving this parity is to face the flipped edge on the top layer and apply the algorithm Rw U2, X, Rw U2, Rw U2, Rw' U2, Lw U2, Rw' U2, Rw U2, Rw' U2, Rw'.
- PLL Swap Parity: Two edges need to be swapped. Again, there’s a particular sequence of moves to correct this, which are r2, U2, r2, Uw2, r2, u2.
For both cases, it's necessary to memorize the required algorithms and have them on your muscle memory when solving.
Step 5 - Practice, Practice, Practice
Like all Rubik's Cube solutions, the key to mastery is repetition. The more you practice, the more familiar you'll become with patterns, cases, and parities and the quicker and more efficiently you'll be able to solve the cube.
The 4x4 Rubik's Cube might seem intimidating at first, but with just a little bit of determination, it becomes very easy to learn! Try to watch heaps of example solves from various cubers so that you can learn tons of techniques on how to handle several cases.
Sarthak Masta is a speedcuber from Raipur. He started cubing in 2013 and now has 9 years of cubing experience. Apart from cubing, Sarthak enjoys making music and singing. He has attended a total of 7 competitions in Raipur and has gotten 10 podiums, with 2 gold medals, 4 silver medals and 4 bronze medals.