head to head
Neither is meaningfully harder - they pose close to the same test. The widest gap is execution, and it is a single point.

Execution · Pure Mechanics
A falling-capsule puzzle testing speed placement to clear virus layouts.

Execution · Pure Mechanics
Battle royale Tetris where raw stacking speed decides who outlasts 98 opponents.
Dr. Mario Online Rx leans Execution (Pure Mechanics); Tetris 99 leans Execution (Pure Mechanics).
Tetris 99 leans a little harder on execution, though the gap is small.
Dr. Mario Online Rx
Fast capsule placement under speed-up is the lead skill
Tetris 99
High-speed stacking and finesse define survival
Tetris 99 leans a little harder on reads, though the gap is small.
Dr. Mario Online Rx
Versus play adds light anticipation of opponent tempo
Tetris 99
Targeting and badge timing against humans matter mid-match
Same score on variance - which means the number cannot separate them. The difference is in what each one asks of you.
Dr. Mario Online Rx
Capsule colors are random but quickly mappable
Tetris 99
Incoming garbage timing and piece sequence add chaos
Same score on optimization - which means the number cannot separate them. The difference is in what each one asks of you.
Dr. Mario Online Rx
Clearing virus layouts has known efficient patterns
Tetris 99
Stacking theory and downstack efficiency are studied skills
A matching score does not mean a matching test. Two games can both sit at 10 on execution and demand completely different things of you - which is why the reasoning above matters more than the number beside it.