diff --git a/rpgpack/commands/roll.py b/rpgpack/commands/roll.py
index bb69dd8f..54d48ee7 100644
--- a/rpgpack/commands/roll.py
+++ b/rpgpack/commands/roll.py
@@ -15,14 +15,21 @@ class RollCommand(Command):
     async def run(self, args: CommandArgs, data: CommandData) -> None:
         first: typing.Optional[str] = args.optional(0)
         second: typing.Optional[str] = args.optional(1)
-        if second:
-            minimum = int(first)
-            maximum = int(second)
-        elif first:
-            minimum = 1
-            maximum = int(first)
-        else:
-            minimum = 1
-            maximum = 100
+        try:
+            if second:
+                minimum = int(first)
+                maximum = int(second)
+            elif first:
+                minimum = 1
+                maximum = int(first)
+            else:
+                minimum = 1
+                maximum = 100
+        except ValueError:
+            if isinstance(first, str) and "d20" in first:
+                raise InvalidInputError(f"Invalid value specified.\n"
+                                        f"Were you looking for [c]{self.interface.prefix}dice[/c]?")
+            else:
+                raise InvalidInputError("Invalid value specified.")
         result = random.randrange(minimum, maximum+1)
         await data.reply(f"🎲 Dice roll [{minimum}-{maximum}]: [b]{result}[/b]")