Post Crocomire Jump Room
|Post Crocomire Shaft|
|Grapple Beam Room||Adjacent rooms|
The optimal strategy is to run off of the ramp, shoot the door in mid-air, and mockball through. Then coming back, use the Grappling Beam on the Rippers to swing over to the missile pack.
If you're not comfortable with the Grappling strategy, an alternative is to do a running jump off the ramp up to the missile platform, then fall back down and run off the ramp a second time to the Grapple Beam Room. After getting the Grappling Beam, an appropriately-timed jump will allow for a mockball under the speed blocks and Mellas, while avoiding the Rippers.
Since this missile pack generally isn't taken in RBO, the alternate strategy given above is the optimal path (except with a mockball going into the Grapple Beam Room).
With only Speedbooster and Power Bombs, you can shinespark up to the missile platform before dropping down, wall jumping up a bit, and horizontally shinesparking to the Grappling Beam Room door. The missile platform overhangs the ramp, so both shinesparks will need to be activated mid-air.
You can use a short charge to destroy the Speed Booster blocks on the lower level without even having Power Bombs, but this will require an extremely short charge, such as a stutter-3.
You can also reach either of these platforms with an Infinite Bomb Jump, with no items other than Morph Ball and Bombs.