Using glitch opcodes of the processor is a very nice touch! For those who are not aware: 6502 was hand-designed. There are many opcodes that are not documented

Using glitch opcodes of the processor is a very nice touch! For those who are not aware: 6502 was hand-designed. There are many opcodes that are not documented (they were the "do not care" squares in the karnaugh maps and PALs used to create various internal control signals). This means that many still do something. Over the years many were documented well, and this code uses some of them, which is super cool! It does mean that this code will not work on later 6502 variants like the 65c02 which act differently when faced with those opcode.