|Halfie Climb Room||Adjacent rooms||Draygon Save Room
The Precious Room
Halfie & Full Halfie
The halfie is a trick that involves performing a shinespark to travel halfway through the Colosseum by gaining speed from the Botwoon Energy Tank Room, entering the Halfie Climb Room, charging the spark near the vertical wall of pipes once inside, quickly climbing the pipes with walljumps, opening the top right door, and shinesparking through it.
As people improve at executing this trick, they will become capable of performing the full halfie, which involves running through the top right door and jumping in the air, all while maintaining a shinespark charge, in order to have the shinespark carry them the entire distance of the Colosseum (as normally, the "P-shaped" pipe formation blocks the (Halfie) shinespark from traveling beyond that point). This technique used to be thought of as "TAS only" because of how much it requires swift walljumping and a clean grab (such as that of a downgrab) of the platform before the top right door in order to pull it off.
The halfie costs ~60 energy and the full halfie (almost always) costs 127 energy when completed.
When walljumping, the speed at which you rise is determined by how long and how often you release the jump button. You want to release it for as short a time as possible. You also want to perform another walljump before your jump velocity decreases too much; however, you do not want to walljump so much that you spend too much time with the jump button released. A recommended amount of walljumps for performing either trick is between four and six; however, more important than the amount is that the walljumps are quick and efficient.
An alternative strategy for the full halfie that is considered TAS only is to freeze all of the Mochtroids in the Halfie Climb Room so that they form a bridge leading towards the top right door, and perform a short charge with their assistance.
Historically, some runners used to use a Gravity Jump to set up the Full Halfie instead of walljumps; this does save time for IGT runs, but is slower RTA than even the standard Halfie.
The optimal strategy for this room when returning from Draygon is to do a shinespark from the top right of the room all the way to the left door, similar to the full halfie. To pull off this trick a blue suit must be acquired during the Draygon fight.
Most people activate the shinespark charge in the previous room to be able to start run and jump higher, reaching the top of the rightmost pillar faster. The shinespark can then be activated either mid-air or while standing on the ground (a crouched shinespark will be too high).
The reverse halfie costs ~110 energy, a bit less than full halfie since it's a bit shorter.
An alternative to the reverse halfie is to use space jump if it has been collected (e.g. in 100% or Any% KPDR). The fastest way, called whomple jump, is when Samus jumps as soon as she enters the room and keeps space jumping without touching any of the pillars. It is a precise trick, where as much running speed as possible must be gathered from the door ledge in the previous room, and it requires both speed booster and hi-jump boots activated.
Optimally a Blue Suit for the reverse halfie will save about 2.5 seconds, but that will depend on execution. The difference is about 1.5 seconds in this comparison:
If you miss the initial jump for the Whomple, you should build up as much run speed as possible from the first platform, and Space Jump across. This can be as little as 1 second slower than the Whomple.