As in, that mini-game that was included with the entire Super Mario Advance series, and M&L1 as well?
Today I achieved a new high score: 553570, phase 56.
I hadn't played it in years. My previous record was... phase 43 I believe? (I would need to get out all 5 GBA games and check... Not that it really matters anymore.)
I accidentally picked up the POW block in phase 50. Lost 4 lives there. (It's good there was a bonus level on phase 51, or the Game Over would have been soon after that... But I was playing with one life remaining from 52 or 53 onward.)
By the way, the difficulty seems to even out starting at phase 40.
Phase 1: Spinies appear
Phase 5: Crabs appear (possibly fireballs, though I believe they appear in 1-3 if you wait long enough)
Phase 7: Fighter Flies appear
Phase 10: Freezies appear
Phase 17: Icicles appear; top 2 platforms are permanently frozen except on bonus levels
Phase 20: 2 icicles can appear at once
Phase 24: Enemies recover much more quickly
Phase 31: 3 icicles can appear at once
Phase 40: 4 icicles can appear at once
Bonus levels: Phases 4, 9, 16, 23, 30, 37, 44, 51,...