Hot and Cold is the third subchapter of Chapter 8: Core in Celeste. The subchapter is mostly just a continuation of the last one with no new mechanics introduced. There are no story moments found in this subchapter.
Gameplay[]
This subchapter is quite short, consisting of just five required rooms. Most of these rooms will task the player with flipping hot/cold switches midway through the room to change all of the objects to their opposite counterparts and continue the platforming like that. The fourth room of the subchapter is actually quite tricky; it consists of many columns of ice balls, with bumpers and dash crystals found inbetween some. The player should already know about holding down the jump button to get a larger bounce on ice balls, but aside from that the most critical advice is to just play safely and patiently. Waiting atop bumpers for when the time is right is very helpful to make it by.
Strawberries[]
There are 3 Strawberries found in this subchapter.
Berry 1
At the end of the first room of the subchapter, a transition at the top of the right side can be seen, blocked by a magma barrier. To get past this, continue onward into the next room until you reach the hot/cold switch, then hit it and bounce back to the left on the created ice balls. Make it back to the first room of the subchapter, then dash up to the vertical transition. In the following room, many bumpers are seen above a spike floor and corridors above them are surrounded by ice walls. This Strawberry is in the farthest right of these ice wall corridors. There is a plethora of ways to approach this berry, but the most reliable way is to wall jump off of the floating platform's ice walls to get over to the bumper area without using a dash, then use both of your dashes to reach the Strawberry. You can also barely reach this area by bouncing on the rightmost bumper and wall jumping. From there, bounce on the top-left side of the right bumper and move over to the left safely, returning to the start with either the wall jumping from earlier or a risky bounce on the left side of the leftmost bumper.
Berry 2
Found in the third room of the subchapter, you can find this berry at the end of the room floating at the top. After being bounced by the last bumper in the room, you should be in range to dash straight up into the Strawberry and collect it.
Berry 3
This Strawberry is located above the fourth room of the subchapter, which can be accessed in a small hole not far to the left of the hot/cold switch. It's easily enterable when the room is cold, but this will block off the Strawberry with an ice barrier, forcing you to go left and restart the prior room. The actual way to get this berry won't be so simple, as you need to enter the room while it's hot. Bounce on some ice balls near the hot/cold switch while still having both dashes available to get up to it and change the room the hot. Then, start moving to the left with dashes and stalling properly until there's an opening to get up around any potential fire balls. After that, the berry is there to be collected and you can head to the right to fall to the end of the lower room.