Face

Face is a programming language that is made up of entirely faces, there are 16 faces in total and are used as commands and arguments or seperators. There is also one value int

Each face, apart from =( and ;) can either be a command or an argument. As arguments the faces turn into numbers or characters and are evaluated as a mathematical expression.

:)
1
:(
2
:]
3
;(
4
:P
5
;P
6
XD
7
:D
8
;D
9
:O
0
:o
+
;O
-
;o
*
=)
/

And they can be used as commands as so:

:) [faces] =(
Prints out character that is passed in faces
:( [faces] =(
Prints out number that is passed in faces
:] [faces] =(
Prints out the face that was passed in
;( [commands] ;)
Runs the commands inside the loop until the value is 0
:P [faces] =(
Sets value to the int passed in
;P =(
Prints the value as a character
XD =(
Exits the program
:D [faces] =(
Prints charager that was passed in with newline at the end
;D =(
Prints a newline
:O [faces] =(
Add int passed in to value
:o [faces] =(
Subtract int passed in from value
;O [faces] =(
Multiplies int passed in and value
;o [faces] =(
Divide value by int passed in
=) =(
Set value to int from character user inputs

And this is "Hello World!":

:P :) :O :D =( :) XD :( =( :) :) :O :) =( ;P =( ;P =( :) :) :) :) =( :) :] :( =( :) :D XD =( :) :) :) :) =( :) :) :) ;( =(= ;P =( :) :) :O :O =( :D :] :] =(

Here Deobfuscated and with comments:

:P :) :O :D =( <- Set value to "l"
:) XD :( =( <- "H"
:) :) :O :) =( <- "e"
;P =( <- Get value or "l"
;P =( <- Get value or "l"
:) :) :) :) =( <- "o"
:) :] :( =( <- " "
:) :D XD =( <- "W"
:) :) :) :) =( <- "o"
:) :) :) ;( =( <- "r"
;P =( <- Get value or "l"
:) :) :O :O =( <- "d"
:D :] :] =( <- "!" with newline at the end

Here is the python interpreter.