APB

 APB method Information about the method Proposer(s): James Straughan Proposed: 2021 Alt Names: none Variants: APB-CDRLL No. Steps: 5 or 6 (depending on LL) No. Algs: 24-672 Avg Moves: ~48 Purpose(s): Speedsolving

APB (Athefre's pair and block) is a 3x3 speedsolving method invented by James Straughan. It is based on 2x2x3 blockbuilding and algorithms resulting in a high TPS.

Steps

1. 223: Build a 2x2x3 block on the left. The current recommended way to do this is to solve a Roux First Block in dL and add the DF and DB edges. Another way is to build a 2x2x2 then extend to a 2x2x3.
2. dBR pair: Create an F2L pair that belongs at back (the DBR corner + the BR edge) and keep it on the U layer.
3. EOPair: Orient all edges while inserting the pair. There are 63 total cases averaging 5.76 moves.
4. LXS: Solve the final three pieces (FR + DR edge + DFR corner) of the F2L. This step contains 116 algorithms averaging around 8.59 moves.
5. LL: Solve the last layer using any LL method. Since the edges are already oriented, the solver can use ZBLL which has 493 algorithms. Another approach is OCLL + PLL which has 28 algorithms and COLL + EPLL which has 46 algorithms.

Variants

1. APB-CDRLL is a variant of APB that uses CDRLL and L5EP

1. 223: Build 2x2x3 block on the left. Itâ€™s usually good to do a Roux FB and finish the 2x2x3 by solving the DF and DB edges.
2. dBR pair: Create an F2L pair that belong at back (DBR+BR) and keep it on the U layer.
3. EOPair: Orient all edges while inserting the pair. There are 63 total cases averaging 5.76 moves.
4. dFR pair: Create an F2L pair on the front (DFR+FR).
5. CDRLL: Solve the last layer corners while ignoring the DR edge. CDRLL contains 42 algorithms averaging around 11 moves.
6. L5EP: Solve the 5 remaining edges. L5EP contains 16 algorithms.

2. APB-LEORCP is a combination between APB and LEOR which allows for much lower algorithm count and mid solve CP

1. 1X2X3 block: build 1x2x3 Block at the left or the right (it better being at the opposite side of your dominant hand) this step is the same as Roux and LEOR
2. EOStripe: Orient all edges while simultaneously solving DF and DB. this step is the same as LEOR
3. CPPair: solve the back pair (usually the RB edge along with the DRB corner) while permuting all of the corners. The beginner way to do it uses 10 algorithms to solve a paired pair and doing CP. the advanced way uses 210 algorithms and solve the CPPair from any case possible.
4. LXS: Solve the final three pieces (usually the FR + DR edge + DFR corner) of the F2L. This step contains 116 algorithms averaging around 8.59 moves. This step is completely RU(S) gen.
5. 2GLL: solve the last layer using 84 algorithms that uses only RU(S) gen.

3. APB-CP is a variant of APB that uses CP to do 2GLL. The method has about 830 algorithms.

1. 223: Build a 2x2x3 block on the left. The current recommended way to do this is to solve a Roux First Block in dL and add the DF and DB edges. Another way is to build a 2x2x2 then extend to a 2x2x3.
2. dBR pair: Create an F2L pair that belongs at back (the DBR corner + the BR edge) and keep it on the U layer.
3. EOCPair: Orient all edges while permuting all of the corners while inserting the pair. There are 630 total cases.
4. LXS: Solve the final three pieces (FR + DR edge + DFR corner) of the F2L. This step contains 116 algorithms averaging around 8.59 moves.
5. 2GLL: solve the last layer with 84 algorithms consisting of R U S moves.

Pros

• Mostly algorithms, which is 70-75% of the solve
• Good ergonomics, allowing for higher TPS
• No rotation required
• Low movecount

Cons

• High algorithm count
• Mid solve EO, although a solver can easily get good at EO recognition by tracking the FR edge while creating the pair that belongs in the back, hence making EO recognition very easy.
• Since it's a very new method the algorithms are not very developed and because of that tutorials are lacking.