head to head
vs
Half-Life 2vsSonic Free Riders
Half-Life 2 leans Execution (Pure Mechanics); Sonic Free Riders leans Execution (Pure Mechanics).
Half-Life 2Sonic Free Riders
Axis by axis
Execution6 vs 6
Even - both lean on execution about the same.
Reads1 vs 1
Even - both lean on reads about the same.
Variance1 vs 2
Sonic Free Riders leans harder on variance: Item pickups inject kart-style randomness
Optimization3 vs 2
Half-Life 2 leans harder on optimization: Linear progression with no builds.
Two games can score the same on an axis and still test it in very different ways - read each rationale, not just the number.