diff --git a/src/constants.rs b/src/constants.rs
index f108f93..3b6c4e6 100644
--- a/src/constants.rs
+++ b/src/constants.rs
@@ -19,7 +19,7 @@ pub const ROOM_MIN_WIDTH: usize = 4;
 pub const ROOM_MIN_HEIGHT: usize = 4;
 
 /// How many levels does the dungeon have?
-pub const LEVELS: usize = 2;
+pub const LEVELS: usize = 4;
 
 /// length of a game frame in ms
 pub const FRAME_LENGTH: u64 = 100;
@@ -46,6 +46,12 @@ pub fn get_monsters_per_level() -> Vec<HashMap<MonsterTypes, std::ops::RangeIncl
             (MonsterTypes::Skeleton, 33),
             (MonsterTypes::Snake, 33),
         ],
+        // level 4
+        vec![
+            (MonsterTypes::Orc, 34),
+            (MonsterTypes::Skeleton, 33),
+            (MonsterTypes::Snake, 33),
+        ],
     ];
     if tmp.len() < LEVELS {
         panic!(
@@ -79,8 +85,8 @@ pub fn get_room_type_per_level() -> Vec<HashMap<RoomType, std::ops::RangeInclusi
         // level 1
         vec![
             (RoomType::EmptyRoom, 50),
-            (RoomType::ArtifactRoom, 25),
-            (RoomType::MonsterRoom, 5),
+            (RoomType::ArtifactRoom, 10),
+            (RoomType::MonsterRoom, 20),
             (RoomType::BasicRoom, 20),
         ],
         // level 2
@@ -91,7 +97,17 @@ pub fn get_room_type_per_level() -> Vec<HashMap<RoomType, std::ops::RangeInclusi
             (RoomType::ArtifactRoom, 13),
         ],
         // level 3
-        vec![(RoomType::EmptyRoom, 50), (RoomType::MonsterRoom, 50)],
+        vec![
+            (RoomType::EmptyRoom, 50),
+            (RoomType::BasicRoom, 25),
+            (RoomType::MonsterRoom, 25),
+        ],
+        // level 4
+        vec![
+            (RoomType::BasicRoom, 33),
+            (RoomType::MonsterRoom, 33),
+            (RoomType::ArtifactRoom, 34),
+        ],
     ];
     if tmp.len() < LEVELS {
         panic!(
diff --git a/src/level.rs b/src/level.rs
index b2b03f0..67946da 100644
--- a/src/level.rs
+++ b/src/level.rs
@@ -57,7 +57,7 @@ impl Level {
             return (None, None, None);
         }
         if !self.discovered[x][y] {
-            #[cfg(test)]
+            // #[cfg(test)]
             return (Some(StructureElement::Unknown), None, None);
         }
         let search_pos = &Position::new(self.level, x, y);
diff --git a/src/level_generator.rs b/src/level_generator.rs
index f63240d..883b2b1 100644
--- a/src/level_generator.rs
+++ b/src/level_generator.rs
@@ -1,5 +1,6 @@
 use petgraph::algo::min_spanning_tree;
 use petgraph::data::*;
+use petgraph::graph::Edge;
 use petgraph::graph::Graph;
 use petgraph::graph::UnGraph;
 
@@ -139,6 +140,11 @@ impl LevelGenerator {
         rng: &mut ThreadRng,
         rooms: &[[Room; ROOMS_VERTICAL]; ROOMS_HORIZONTAL],
     ) -> GeneratorGraph {
+        // calculate the weight of an edge
+        fn calc_edge_weight(delta: usize) -> usize {
+            delta * delta
+        }
+
         let mut graph: GeneratorGraph = UnGraph::<(usize, usize), usize>::default();
         for (col, tgt_col) in rooms.iter().enumerate().take(ROOMS_HORIZONTAL) {
             for (row, room) in tgt_col.iter().enumerate().take(ROOMS_VERTICAL) {
@@ -166,8 +172,7 @@ impl LevelGenerator {
                                 graph.add_edge(
                                     src_index,
                                     tgt_index,
-                                    (rng.gen_range(0..5) as f32 / 5.0) as usize
-                                        * col.abs_diff(col_1),
+                                    calc_edge_weight(col.abs_diff(col_1)),
                                 );
                                 break;
                             }
@@ -181,8 +186,7 @@ impl LevelGenerator {
                                 graph.add_edge(
                                     src_index,
                                     tgt_index,
-                                    (rng.gen_range(0..5) as f32 / 5.0) as usize
-                                        * row.abs_diff(row_1),
+                                    calc_edge_weight(row.abs_diff(row_1)),
                                 );
                                 break;
                             }
@@ -191,8 +195,35 @@ impl LevelGenerator {
                 }
             }
         }
-        Graph::from_elements(min_spanning_tree(&graph))
-        // graph
+        let mut mst: GeneratorGraph = Graph::from_elements(min_spanning_tree(&graph));
+
+        // readd some of the short edges that were remove (all between a weight of 1 to 10)
+        let initial_edges = graph.raw_edges();
+        let minimal_edges = mst.raw_edges();
+        let mut extra_edges: Vec<Edge<usize>> = vec![];
+        for init_edge in initial_edges {
+            let start_node = init_edge.source();
+            let end_node = init_edge.target();
+            let mut found = false;
+            for min_edge in minimal_edges {
+                if min_edge.source() == start_node && min_edge.target() == end_node {
+                    found = true;
+                    break;
+                }
+            }
+            if !found {
+                extra_edges.push(init_edge.clone());
+            }
+        }
+        extra_edges.sort_by(|a, b| a.weight.cmp(&b.weight));
+        for e in extra_edges
+            .iter()
+            .filter(|x| x.weight > 1)
+            .filter(|x| x.weight < 7)
+        {
+            mst.add_edge(e.source(), e.target(), e.weight);
+        }
+        mst
     }
 
     fn create_connections(