Reti Opening Advance Variation (1.Nf3 d5 2.c4 d4 / 1.Nf3 d5 2.c4 d4 3.b4 c5) Chess Puzzles

The reti opening advance variation is a Reti Opening sideline where White meets Black's central setup with an early advance of the d-pawn, usually aiming to claim space and steer the game away from pure flank play. I should be honest: this is a less standardized branch of the Reti, and the exact move order is not as widely documented as the mainline Reti structures, so the defining feature is the early central advance rather than a single universally fixed sequence.