diff --git a/src/core/operations/BifidCipherDecode.mjs b/src/core/operations/BifidCipherDecode.mjs
deleted file mode 100644
index 29318a32..00000000
--- a/src/core/operations/BifidCipherDecode.mjs
+++ /dev/null
@@ -1,125 +0,0 @@
-/**
- * @author Matt C [matt@artemisbot.uk]
- * @copyright Crown Copyright 2018
- * @license Apache-2.0
- */
-
-import Operation from "../Operation.mjs";
-import { genPolybiusSquare } from "../lib/Ciphers.mjs";
-import OperationError from "../errors/OperationError.mjs";
-
-/**
- * Bifid Cipher Decode operation
- */
-class BifidCipherDecode extends Operation {
-
-    /**
-     * BifidCipherDecode constructor
-     */
-    constructor() {
-        super();
-
-        this.name = "Bifid Cipher Decode";
-        this.module = "Ciphers";
-        this.description = "The Bifid cipher is a cipher which uses a Polybius square in conjunction with transposition, which can be fairly difficult to decipher without knowing the alphabet keyword.";
-        this.infoURL = "https://wikipedia.org/wiki/Bifid_cipher";
-        this.inputType = "string";
-        this.outputType = "string";
-        this.args = [
-            {
-                "name": "Keyword",
-                "type": "string",
-                "value": ""
-            }
-        ];
-    }
-
-    /**
-     * @param {string} input
-     * @param {Object[]} args
-     * @returns {string}
-     *
-     * @throws {OperationError} if invalid key
-     */
-    run(input, args) {
-        const keywordStr = args[0].toUpperCase().replace("J", "I"),
-            keyword = keywordStr.split("").unique(),
-            alpha = "ABCDEFGHIKLMNOPQRSTUVWXYZ",
-            structure = [];
-
-        let output = "",
-            count = 0,
-            trans = "";
-
-        if (!/^[A-Z]+$/.test(keywordStr) && keyword.length > 0)
-            throw new OperationError("The key must consist only of letters in the English alphabet");
-
-        const polybius = genPolybiusSquare(keywordStr);
-
-        input.replace("J", "I").split("").forEach((letter) => {
-            const alpInd = alpha.split("").indexOf(letter.toLocaleUpperCase()) >= 0;
-            let polInd;
-
-            if (alpInd) {
-                for (let i = 0; i < 5; i++) {
-                    polInd = polybius[i].indexOf(letter.toLocaleUpperCase());
-                    if (polInd >= 0) {
-                        trans += `${i}${polInd}`;
-                    }
-                }
-
-                if (alpha.split("").indexOf(letter) >= 0) {
-                    structure.push(true);
-                } else if (alpInd) {
-                    structure.push(false);
-                }
-            } else {
-                structure.push(letter);
-            }
-        });
-
-        structure.forEach(pos => {
-            if (typeof pos === "boolean") {
-                const coords = [trans[count], trans[count+trans.length/2]];
-
-                output += pos ?
-                    polybius[coords[0]][coords[1]] :
-                    polybius[coords[0]][coords[1]].toLocaleLowerCase();
-                count++;
-            } else {
-                output += pos;
-            }
-        });
-
-        return output;
-    }
-
-    /**
-     * Highlight Bifid Cipher Decode
-     *
-     * @param {Object[]} pos
-     * @param {number} pos[].start
-     * @param {number} pos[].end
-     * @param {Object[]} args
-     * @returns {Object[]} pos
-     */
-    highlight(pos, args) {
-        return pos;
-    }
-
-    /**
-     * Highlight Bifid Cipher Decode in reverse
-     *
-     * @param {Object[]} pos
-     * @param {number} pos[].start
-     * @param {number} pos[].end
-     * @param {Object[]} args
-     * @returns {Object[]} pos
-     */
-    highlightReverse(pos, args) {
-        return pos;
-    }
-
-}
-
-export default BifidCipherDecode;