Shield drop
Shield platform dropping is an advanced technique in Super Smash Bros. and Super Smash Bros. Brawl. It involves dropping through a soft platform while shielding.
In SSB
The technique is simple, as there is no sidestepping in SSB.
In SSBB
In Brawl, because pressing the control stick too far and too fast results in a sidestep, the timing and precision required is extremely strict - one must move the control stick down to 68.75% of its maximum downwards angle in 6 frames without moving it past 70% of said angle in 4 frames.
Uses
Shield platform dropping opens a larger possibility of comboing, techchasing, edgeguarding and mindgaming. The player can run and pass under the platform, which cannot be done without shielding. This technique is not well known, so those who do know it can trick people with it.