24 games ranked by how much the tags Steam players vote on them overlap with BEAT 'EM DOWN's. A rare tag counts for far more than one that sits on half the store, and popularity never moves a game up.
What they share most: Rhythm, Music-Based Procedural Generation, Arcade, FPS, Shooter, Abstract.

1·MUSYNX
85% match · Rhythm, Music-Based Procedural Generation
89% of 6,824 reviews positive

2·Melody's Escape 2
83% match · Music-Based Procedural Generation, Rhythm
92% of 350 reviews positive

3·Hyperspace Invaders II: Pixel Edition
83% match · Music-Based Procedural Generation, Rhythm
81% of 405 reviews positive

4·Soundodger+
82% match · Music-Based Procedural Generation, Rhythm
90% of 815 reviews positive

5·Beat Hazard
82% match · Music-Based Procedural Generation, Rhythm
95% of 7,452 reviews positive

6·Beat Hazard 2
81% match · Music-Based Procedural Generation, Rhythm
86% of 2,259 reviews positive

7·Audiosurf 2
80% match · Music-Based Procedural Generation, Rhythm
83% of 6,050 reviews positive

8·Project Rhombus
80% match · Rhythm, Abstract
93% of 1,400 reviews positive

9·Audioshield
80% match · Music-Based Procedural Generation, Rhythm
81% of 2,739 reviews positive

10·64.0
79% match · Rhythm, Abstract
90% of 1,492 reviews positive

11·AudioSurf
78% match · Rhythm, Music-Based Procedural Generation
96% of 11,106 reviews positive

12·Music Racer
78% match · Music-Based Procedural Generation, Rhythm
88% of 3,625 reviews positive

13·Melody's Escape
78% match · Music-Based Procedural Generation, Rhythm
93% of 4,801 reviews positive

14·Rift of the NecroDancer
78% match · Rhythm, Music-Based Procedural Generation
94% of 6,347 reviews positive

15·Melatonin
77% match · Rhythm, Music-Based Procedural Generation
94% of 8,203 reviews positive

16·Riff Racer - Race Your Music!
77% match · Music-Based Procedural Generation, Rhythm
81% of 2,060 reviews positive

17·BPM: BULLETS PER MINUTE
76% match · Rhythm, FPS
90% of 11,432 reviews positive

18·The Polynomial - Space of the music
76% match · Rhythm, Music-Based Procedural Generation
73% of 500 reviews positive

19·Groove Coaster
76% match · Rhythm, Arcade
67% of 1,606 reviews positive

20·Beat Saber
76% match · Rhythm, Music-Based Procedural Generation
95% of 76,364 reviews positive · 403 playing

21·Retro/Grade
76% match · Rhythm, Arcade
84% of 395 reviews positive

22·Hatsune Miku: Project DIVA Mega Mix+
76% match · Rhythm, Arcade
95% of 23,844 reviews positive

23·Symphony
75% match · Rhythm, Music-Based Procedural Generation
84% of 1,494 reviews positive

24·Sound Slide
75% match · Rhythm, Free to Play
78% of 513 reviews positive
The closest matches to BEAT 'EM DOWN on Steam are MUSYNX, Melody's Escape 2, Hyperspace Invaders II: Pixel Edition, Soundodger+, Beat Hazard. They rank highest because their Steam community tags overlap most with BEAT 'EM DOWN's, and shared tags include Rhythm, Music-Based Procedural Generation, Arcade.
Every game is described by the tags Steam players vote on it. Rare, specific tags such as Rhythm, Music-Based Procedural Generation, Arcade count far more than catch-all ones like "Indie" or "Singleplayer", and each game is scored on how closely its whole tag profile matches BEAT 'EM DOWN's. Popularity never affects the ranking.