diff --git a/src/euler84/src/lib.rs b/src/euler84/src/lib.rs
index 786152b..b61baa7 100644
--- a/src/euler84/src/lib.rs
+++ b/src/euler84/src/lib.rs
@@ -92,8 +92,9 @@ enum Chance {
     DoNothing6,
 }
 
+#[allow(dead_code)]
 #[derive(Debug)]
-enum Dice {
+pub enum Dice {
     FourSided = 4,
     SixSided = 6,
 }
@@ -126,14 +127,16 @@ impl Monopoly {
     }
 
     #[allow(clippy::new_without_default)]
-    pub fn new() -> Self {
+    pub fn new(dice: Dice) -> Self {
         let mut rng = rand::thread_rng();
         let community_pile = Self::gen_random_community_pile(&mut rng);
         let chance_pile = Self::gen_random_chance_pile(&mut rng);
+        let mut board = Squares::iter().cycle();
+        let _ = board.next(); // make sure we are on "Go"
         Self {
             rng,
-            board: Squares::iter().cycle(),
-            dice: Dice::SixSided,
+            board,
+            dice,
             community_pile,
             chance_pile,
             number_consecutive_doubles: 0,
@@ -159,7 +162,7 @@ impl Monopoly {
             return self.go_to_jail();
         }
 
-        let square = self.board.nth(distance).unwrap();
+        let square = self.advance_by(distance);
         match square {
             Squares::G2J => self.go_to_jail(),
             Squares::CC1 => self.handle_community_chest(Squares::CC1),
@@ -193,8 +196,7 @@ impl Monopoly {
     }
 
     fn go_to_square(&mut self, square: Squares) -> Squares {
-        let _ = (&mut self.board).skip_while(|c| *c != square);
-        square
+        self.board.find(|c| *c == square).unwrap()
     }
 
     fn go_to_squares(&mut self, squares: &[Squares]) -> Squares {
@@ -251,9 +253,8 @@ impl Monopoly {
         }
     }
 
-    #[cfg(test)]
-    fn advance_by_number(&mut self, number: usize) -> Squares {
-        self.board.nth(number).unwrap()
+    fn advance_by(&mut self, number: usize) -> Squares {
+        self.board.nth(number - 1).unwrap()
     }
 }
 
@@ -268,7 +269,7 @@ impl Statistics {
         Self {
             monopoly,
             iterations,
-            fields_count: HashMap::from_iter(Squares::iter().zip([0].into_iter().cycle())),
+            fields_count: Squares::iter().zip([0].into_iter().cycle()).collect(),
         }
     }
 
@@ -293,19 +294,19 @@ impl Statistics {
 }
 
 #[cfg(test)]
-pub mod test {
-    use super::{Monopoly, Squares};
+mod test {
+    use super::{Dice, Monopoly, Squares, NUMBER_SQUARES};
 
     #[test]
     fn jail() {
-        let mut monopoly = Monopoly::new();
+        let mut monopoly = Monopoly::new(Dice::SixSided);
         assert_eq!(monopoly.go_to_jail(), Squares::Jail);
         assert_eq!(monopoly.go_to_jail(), Squares::Jail);
     }
 
     #[test]
     fn utility() {
-        let mut monopoly = Monopoly::new();
+        let mut monopoly = Monopoly::new(Dice::SixSided);
         assert_eq!(monopoly.go_to_utility(), Squares::U1);
         assert_eq!(monopoly.go_to_utility(), Squares::U2);
         assert_eq!(monopoly.go_to_utility(), Squares::U1);
@@ -313,7 +314,7 @@ pub mod test {
 
     #[test]
     fn railway() {
-        let mut monopoly = Monopoly::new();
+        let mut monopoly = Monopoly::new(Dice::SixSided);
         assert_eq!(monopoly.go_to_railway(), Squares::R1);
         assert_eq!(monopoly.go_to_railway(), Squares::R2);
         assert_eq!(monopoly.go_to_railway(), Squares::R3);
@@ -323,18 +324,49 @@ pub mod test {
 
     #[test]
     fn go() {
-        let mut monopoly = Monopoly::new();
+        let mut monopoly = Monopoly::new(Dice::SixSided);
         assert_eq!(monopoly.advance_to_go(), Squares::Go);
         assert_eq!(monopoly.advance_to_go(), Squares::Go);
     }
 
     #[test]
     fn back_3() {
-        let mut monopoly = Monopoly::new();
-        assert_eq!(monopoly.advance_by_number(3) as isize, 3);
+        let mut monopoly = Monopoly::new(Dice::SixSided);
+        assert_eq!(monopoly.advance_by(3) as isize, 3);
         assert_eq!(monopoly.go_back_3_squares(), Squares::Go);
 
-        assert_eq!(monopoly.advance_by_number(27) as isize, 27);
+        assert_eq!(monopoly.advance_by(27) as isize, 27);
         assert_eq!(monopoly.go_back_3_squares() as isize, 24);
     }
+
+    #[test]
+    fn custom() {
+        let mut monopoly = Monopoly::new(Dice::SixSided);
+        assert_eq!(monopoly.go_to_square(Squares::E3), Squares::E3);
+    }
+
+    #[test]
+    fn advance_by() {
+        let mut monopoly = Monopoly::new(Dice::SixSided);
+        assert_eq!(monopoly.advance_by(NUMBER_SQUARES) as isize, 0);
+        assert_eq!(monopoly.advance_by(NUMBER_SQUARES) as isize, 0);
+        assert_eq!(monopoly.advance_by(1) as isize, 1);
+        assert_eq!(monopoly.advance_by(1) as isize, 2);
+        assert_eq!(monopoly.advance_by(1) as isize, 3);
+    }
+
+    #[ignore]
+    #[test]
+    fn rng() {
+        use rand::prelude::*;
+
+        let mut rng = rand::thread_rng();
+
+        let possible_values = Vec::from_iter(0..=5);
+        let mut result = vec![0; 6];
+        for _ in 0..100_000_000 {
+            result[*possible_values.choose(&mut rng).unwrap()] += 1;
+        }
+        println!("{result:?}");
+    }
 }
diff --git a/src/euler84/src/main.rs b/src/euler84/src/main.rs
index 966828e..9981421 100644
--- a/src/euler84/src/main.rs
+++ b/src/euler84/src/main.rs
@@ -1,7 +1,7 @@
 mod lib;
 
 fn main() {
-    let monopoly = lib::Monopoly::new();
+    let monopoly = lib::Monopoly::new(lib::Dice::SixSided);
     let mut statistics = lib::Statistics::new(monopoly, 10_000_000);
     statistics.run();
     statistics.show();