By right clicking with a brick in your main hand, you will throw it as a projectile. Hitting players/entities will damage them, and certain blocks such as glass will break. Bricks can be re-collected after they hit something.
New Old Bricks
Vanilla bricks blocks such as stone bricks, quartz bricks, end stone bricks, etc. now have brick items to go with them and be thrown.
To craft these, just put any bricks block into a crafting table and you can get 4 bricks from them.
This also works the other way, using 4 bricks to craft a bricks block.
You can now encrust bricks in gold and emerald, to make them stronger. These will inflict more damage when thrown at a mob/player, but will not fly as far due to being heavier.
These also have their own blocks naturally (gold/emerald encrusted bricks/stairs/slabs/walls).
Explosive bricks are throwable explosives, essentially being some TNT attached to a brick that can be thrown just like any other in this mod. When these bricks hit something, whether that be a block or an entity, they will explode on contact. They are not as powerful as a block of TNT, sometimes not even able to blow up certain blocks that TNT blocks would otherwise be able to do, but they can be useful as weapons.
To craft these use any 3 bricks of the same type, 3 string, and a block of TNT.
Projectile 3D model:
Buried Bricks, Infested Buried Bricks, & Brick Bugs
Bricks can be found buried close to the surface of the overworld and throughout the nether, perhaps the ruins from past civilizations (is my excuse for them being there).
In the overworld you can find buried normal bricks, gold encrusted bricks, and emerald encrusted bricks.
In the nether you can find buried nether bricks and gold encrusted bricks.
However sometimes these buried bricks can be infested. And if you break these ones, brick bugs will emerge matching the brick type of the buried bricks (eg. normal brick, nether brick, etc.) which will attack you. Just like silver fish, other brick bugs will break out of nearby infested buried bricks, so be careful.
Melee bricks are essentially just bricks on sticks. They do quite a lot of damage and can also be used as pickaxes; They can mine the same ores that a stone pickaxe can.
They can be crafted from any brick item, a stick, and some string.
3D model when in hand of player/entity:
Note, due to the perspectives code no longer working for some reason (and I can't find an alternate way to achieve this as of yet), the 2D item texture isn't in the 1.20.1 version of the mod, only the 3D model is used.
This is a small difference but one that affects the vanilla feel of the mod unfortunately.
Brick Lobbers, Explosive Brick Lobbers, & Friendly Brick Lobbers
Brick lobbers are flying mobs that lob bricks at you, they have normal, nether, and gold variants. The nether and gold ones spawning in the nether.
There are also explosive versions for each type of brick lobber, these as you can probably guess lob explosive bricks rather than ordinary ones.
These only spawn on hard difficulty, and will grief the world if the mob griefing game rule is set to true.
Friendly versions can also be made, these will attack hostile mobs and won't attack you unless you hurt them.
Example of a layout that spawns a friendly brick lobber:
This will make a normal frienly brick lobber, but replace the bricks with nether bricks or gold bricks to get their variants.
Remember to place the Jack O'Lantern last, same as you would with an iron golem or snow golem in vanilla Minecraft.
A friendly nether brick lobber:
Brick golems can spawn naturally in villages using similar conditions to iron golems, they will protect villagers if you attack them and will also attack hostile mobs.
Brick golems can also be created by players similarly to iron golems/snow golems/friendly brick lobbers.
Example of a layout that spawns an emerald brick golem:
Chocolate Bricks, Chocolate Brick Muffins & Chocolate Brick Bunnies
Chocolate bricks are both throwable and edible. While crouched they won't be able to be thrown, making it so you can eat them. When thrown, any players hit with these bricks will be fed them, but be careful because they will still take some damage.
To craft these use 6 cocoa beans.
Chocolate brick muffins are similar to vanilla Minecraft cakes, being placed to be eaten, taking two bites to fully eat.