diff --git a/src/App.css b/src/App.css
index df09300..bae7511 100644
--- a/src/App.css
+++ b/src/App.css
@@ -209,7 +209,7 @@ a:active {
 .Settings-setting {
   margin: 8px;
   display: flex;
-  align-items: center;
+  align-items: top;
 }
 
 .Settings-setting input {
@@ -217,6 +217,11 @@ a:active {
   height: 18px;
 }
 
+.Settings-setting input[type=range] {
+  width: 50px;
+  height: 18px;
+}
+
 .Settings-setting label {
   margin-inline-start: 8px;
 }
diff --git a/src/App.tsx b/src/App.tsx
index b65ec78..5d57a38 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -27,12 +27,13 @@ function useSetting<T>(
 }
 
 function App() {
-  const [page, setPage] = useState<"game" | "about" | "settings">("game");
+  type Page = "game" | "about" | "settings";
+  const [page, setPage] = useState<Page>("game");
   const prefersDark =
     window.matchMedia &&
     window.matchMedia("(prefers-color-scheme: dark)").matches;
   const [dark, setDark] = useSetting<boolean>("dark", prefersDark);
-  const [hard, setHard] = useSetting<boolean>("hard", false);
+  const [difficulty, setDifficulty] = useSetting<number>("difficulty", 0);
 
   useEffect(() => {
     document.body.className = dark ? "dark" : "";
@@ -41,42 +42,42 @@ function App() {
     }, 1);
   }, [dark]);
 
+  const link = (emoji: string, label: string, page: Page) => (
+    <a
+      className="emoji-link"
+      href="#"
+      onClick={() => setPage(page)}
+      title={label}
+      aria-label={label}
+    >
+      {emoji}
+    </a>
+  );
+
   return (
     <div className="App-container">
       <h1>
-        <span style={hard ? { color: "#e66" } : {}}>hell</span>o wordl
+        <span
+          style={
+            difficulty > 0
+              ? {
+                  color: "#e66",
+                  textShadow: difficulty > 1 ? "0px 0px 5px #e66" : "none",
+                }
+              : {}
+          }
+        >
+          hell
+        </span>
+        o wordl
       </h1>
       <div className="top-right">
         {page !== "game" ? (
-          <a
-            className="emoji-link"
-            href="#"
-            onClick={() => setPage("game")}
-            title="Close"
-            aria-label="Close"
-          >
-            ❌
-          </a>
+          link("❌", "Close", "game")
         ) : (
           <>
-            <a
-              className="emoji-link"
-              href="#"
-              onClick={() => setPage("about")}
-              title="About"
-              aria-label="About"
-            >
-              ❓
-            </a>
-            <a
-              className="emoji-link"
-              href="#"
-              onClick={() => setPage("settings")}
-              title="Settings"
-              aria-label="Settings"
-            >
-              ⚙️
-            </a>
+            {link("❓", "About", "about")}
+            {link("⚙️", "Settings", "settings")}
           </>
         )}
       </div>
@@ -114,16 +115,42 @@ function App() {
           </div>
           <div className="Settings-setting">
             <input
-              id="hard-setting"
-              type="checkbox"
-              checked={hard}
-              onChange={() => setHard((x: boolean) => !x)}
+              id="difficulty-setting"
+              type="range"
+              min="0"
+              max="2"
+              value={difficulty}
+              onChange={(e) => setDifficulty(+e.target.value)}
             />
-            <label htmlFor="hard-setting">Hard mode (must use all clues)</label>
+            <div>
+              <label htmlFor="difficulty-setting">Difficulty:</label>
+              &nbsp;
+              <strong>{["Normal", "Hard", "Ultra Hard"][difficulty]}</strong>
+              <div
+                style={{
+                  fontSize: 14,
+                  height: 40,
+                  marginLeft: 8,
+                  marginTop: 8,
+                }}
+              >
+                {
+                  [
+                    `No restrictions on guesses.`,
+                    `Wordle's "Hard Mode". Green letters must stay fixed, and yellow letters must be reused.`,
+                    `An even stricter Hard Mode. Yellow letters must move away, and gray letters can't be reused.`,
+                  ][difficulty]
+                }
+              </div>
+            </div>
           </div>
         </div>
       )}
-      <Game maxGuesses={maxGuesses} hidden={page !== "game"} hard={hard} />
+      <Game
+        maxGuesses={maxGuesses}
+        hidden={page !== "game"}
+        difficulty={difficulty}
+      />
     </div>
   );
 }
diff --git a/src/Game.tsx b/src/Game.tsx
index 921953a..822c669 100644
--- a/src/Game.tsx
+++ b/src/Game.tsx
@@ -4,7 +4,15 @@ import dictionary from "./dictionary.json";
 import { Clue, clue, describeClue, violation } from "./clue";
 import { Keyboard } from "./Keyboard";
 import targetList from "./targets.json";
-import { dictionarySet, pick, resetRng, seed, speak, urlParam } from "./util";
+import {
+  dictionarySet,
+  Difficulty,
+  pick,
+  resetRng,
+  seed,
+  speak,
+  urlParam,
+} from "./util";
 import { decode, encode } from "./base64";
 
 enum GameState {
@@ -16,7 +24,7 @@ enum GameState {
 interface GameProps {
   maxGuesses: number;
   hidden: boolean;
-  hard: boolean;
+  difficulty: Difficulty;
 }
 
 const targets = targetList.slice(0, targetList.indexOf("murky") + 1); // Words no rarer than this one
@@ -111,13 +119,12 @@ function Game(props: GameProps) {
         setHint("Not a valid word");
         return;
       }
-      if (props.hard) {
-        for (const g of guesses) {
-          const feedback = violation(clue(g, target), currentGuess);
-          if (feedback) {
-            setHint(feedback);
-            return;
-          }
+      for (const g of guesses) {
+        const c = clue(g, target);
+        const feedback = violation(props.difficulty, c, currentGuess);
+        if (feedback) {
+          setHint(feedback);
+          return;
         }
       }
       setGuesses((guesses) => guesses.concat([currentGuess]));
diff --git a/src/clue.ts b/src/clue.ts
index 4f283ac..a7896c6 100644
--- a/src/clue.ts
+++ b/src/clue.ts
@@ -1,4 +1,4 @@
-import { ordinal } from "./util";
+import { Difficulty, ordinal } from "./util";
 
 export enum Clue {
   Absent,
@@ -59,21 +59,31 @@ export function describeClue(clue: CluedLetter[]): string {
 }
 
 export function violation(
+  difficulty: Difficulty,
   clues: CluedLetter[],
   guess: string
 ): string | undefined {
+  if (difficulty === Difficulty.Normal) {
+    return undefined;
+  }
   let i = 0;
   for (const { letter, clue } of clues) {
+    const upper = letter.toUpperCase();
+    const nth = ordinal(i + 1);
     if (clue === Clue.Absent) {
-      // Apparently Wordle doesn't enforce this?
-      // if (guess.includes(letter))
-      //   return "Guess can't contain " + letter.toUpperCase();
+      if (difficulty === Difficulty.UltraHard && guess.includes(letter)) {
+        return "Guess can't contain " + upper;
+      }
     } else if (clue === Clue.Correct) {
-      if (guess[i] !== letter)
-        return ordinal(i + 1) + " letter must be " + letter.toUpperCase();
+      if (guess[i] !== letter) {
+        return nth + " letter must be " + upper;
+      }
     } else if (clue === Clue.Elsewhere) {
-      if (!guess.includes(letter))
-        return "Guess must contain " + letter.toUpperCase();
+      if (!guess.includes(letter)) {
+        return "Guess must contain " + upper;
+      } else if (difficulty === Difficulty.UltraHard && guess[i] === letter) {
+        return nth + " letter can't be " + upper;
+      }
     }
     ++i;
   }
diff --git a/src/util.ts b/src/util.ts
index 3ebe6e2..d95c6b8 100644
--- a/src/util.ts
+++ b/src/util.ts
@@ -1,5 +1,11 @@
 import dictionary from "./dictionary.json";
 
+export enum Difficulty {
+  Normal,
+  Hard,
+  UltraHard,
+}
+
 export const maxGuesses = 6;
 
 export const dictionarySet: Set<string> = new Set(dictionary);