diff --git a/share/doc/protocol/create.md b/share/doc/protocol/create.md
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+# Create protocol
+
+## Downstream
+
+| Opcode | Length | Jagex name           | Description                          |
+|-------:|-------:|----------------------|--------------------------------------|
+|      2 |      0 | `OK`                 | Create successful                    |
+|      3 |      0 | Unknown              | Create server offline                |
+|      7 |      0 | `SERVER_FULL`        | Server full                          |
+|      9 |      0 | `IP_LIMIT`           | Too many connections from IP address |
+|     10 |      0 | Unknown              | Date of birth invalid                |
+|     11 |      0 | Unknown              | Date of birth in future              |
+|     12 |      0 | Unknown              | Date of birth this year              |
+|     13 |      0 | Unknown              | Date of birth last year              |
+|     14 |      0 | Unknown              | Country invalid                      |
+|     20 |      0 | Unknown              | Name unavailable                     |
+|     21 | Custom | Unknown              | Name suggestions                     |
+|     22 |      0 | Unknown              | Name invalid                         |
+|     30 |      0 | Unknown              | Password invalid                     |
+|     31 |      0 | Unknown              | Password invalid                     |
+|     32 |      0 | Unknown              | Password guessable                   |
+|     33 |      0 | Unknown              | Password guessable                   |
+|     34 |      0 | Unknown              | Password too similar to username     |
+|     35 |      0 | Unknown              | Password too similar to username     |
+|     36 |      0 | Unknown              | Password too similar to username     |
+|     37 |      0 | `CLIENT_OUT_OF_DATE` | Client out of date                   |
+|     38 |      0 | Unknown              | Cannot create at this time           |
+|     41 |      0 | Unknown              | Email invalid                        |
+|     42 |      0 | Unknown              | Email invalid                        |
+|     43 |      0 | Unknown              | Email invalid                        |
+
+### 2 (`OK`)
+
+### 3 (Create server offline)
+
+**Message:** There was an error contacting the account creation server. Please
+try again.
+
+### 7 (`SERVER_FULL`)
+
+**Message:** The server is currently very busy. Please try again shortly.
+
+### 9 (`IP_LIMIT`)
+
+**Message:** You cannot create an account at this time. Please try again later.
+
+### 10 (Date of birth invalid)
+
+**Message:** Please make sure you have provided a valid date of birth.
+
+### 11 (Date of birth in future)
+
+**Message:** The date of birth is invalid, as it is in the future.
+
+### 12 (Date of birth this year)
+
+**Message:** The date of birth is invalid, as it was this year.
+
+### 13 (Date of birth last year)
+
+**Message:** The date of birth is invalid, as it was last year.
+
+### 14 (Country invalid)
+
+**Mesage:** Please make sure you have provided a valid country.
+
+### 20 (Name unavailable)
+
+**Mesage:** That username is unavailable. Please choose again.
+
+### 21 (Name suggestions)
+
+| Data type    | Description                                                 |
+|--------------|-------------------------------------------------------------|
+| UnsignedByte | Suggested name count (n, must be between 0 and 5 inclusive) |
+| Long\[n\]    | Base37-encoded suggested names                              |
+
+**Message (if n is non-zero):** That username is unavailable. Possible
+alternatives: <comma-separated list of suggested names>.
+
+**Message (if n is zero):** That username is unavailable. We could not suggest a
+suitable alternative account name. Please choose again.
+
+### 22 (Name invalid)
+
+**Message:** Please supply a valid username.
+
+### 30 (Password invalid)
+
+**Message:** Please supply a valid password.
+
+### 31 (Password invalid)
+
+**Message:** Please supply a valid password.
+
+### 32 (Password guessable)
+
+**Message:** Your password is too easy to guess.
+
+### 33 (Password guessable)
+
+**Message:** Your password is too easy to guess.
+
+### 34 (Password too similar to username)
+
+**Message:** Your password is too similar to your username.
+
+### 35 (Password too similar to username)
+
+**Message:** Your password is too similar to your username.
+
+### 36 (Password too similar to username)
+
+**Message:** Your password is too similar to your username.
+
+### 37 (`CLIENT_OUT_OF_DATE`)
+
+**Message:** RuneScape has been updated. Please reload this page.
+
+### 38 (Cannot create at this time)
+
+**Message:** You cannot create an account at this time. Please try again later.
+
+### 41 (Email invalid)
+
+**Message:** Please supply a valid email address.
+
+### 42 (Email invalid)
+
+**Message:** Please supply a valid email address.
+
+### 43 (Email invalid)
+
+**Message:** Please supply a valid email address.