diff --git a/package.json b/package.json
index e357b94..f53993a 100644
--- a/package.json
+++ b/package.json
@@ -1,7 +1,7 @@
 {
-  "name": "building-game",
-  "description": "A blocky, side-scrolling, building and exploration game",
-  "version": "1.0.0",
+  "name": "digging-game",
+  "description": "A blocky, side-scrolling, digging and exploration game",
+  "version": "0.0.1",
   "author": "koehr <n@koehr.in>",
   "license": "MIT",
   "private": true,
diff --git a/src/Field.vue b/src/Field.vue
index a42c49a..06b5b7a 100644
--- a/src/Field.vue
+++ b/src/Field.vue
@@ -13,7 +13,7 @@
 </template>
 
 <script>
-import Level from './lib/level-generator'
+import Level from './level'
 
 const WIDTH = 32
 const HEIGHT = 32
diff --git a/src/level/def.js b/src/level/def.js
new file mode 100644
index 0000000..0670d50
--- /dev/null
+++ b/src/level/def.js
@@ -0,0 +1,28 @@
+export const type = {
+  air: {type: 'air', hp: 0},
+  grass: {type: 'grass', hp: 1},
+  leaves: {type: 'leaves', hp: 1},
+  wood: {type: 'wood', hp: 5},
+  soil: {type: 'soil', hp: 2},
+  gravel: {type: 'gravel', hp: 5},
+  stone: {type: 'stone', hp: 10},
+  bedrock: {type: 'bedrock', hp: 25},
+  cave: {type: 'cave', hp: 0}
+}
+
+export const level = {
+  peak: 24,
+  ground: 28,
+  rock: 32,
+  underground: 48,
+  cave_max: 250
+}
+
+export const probability = {
+  tree: 0.1,
+  soil_hole: 0.3,
+  soil_gravel: 0.2,
+  rock_gravel: 0.1,
+  cave: 0.5,
+  fray: 0.4
+}
diff --git a/src/level/first-iteration.js b/src/level/first-iteration.js
new file mode 100644
index 0000000..33696ea
--- /dev/null
+++ b/src/level/first-iteration.js
@@ -0,0 +1,58 @@
+import SeedRng from 'seedrandom'
+import FastSimplexNoise from 'fast-simplex-noise'
+import {type as T, level as L, probability as P} from './def'
+
+export default class BlockGen {
+  constructor (seed = 'so freakin random') {
+    const simplex = new FastSimplexNoise({ random: SeedRng(seed) })
+    this.rand = (x, y) => 0.5 + 0.5 * simplex.raw2D(x, y)
+  }
+
+  level (level, row, previousRow) {
+    for (let i = 0; i < row.length; i++) {
+      row[i] = this.block(level, i, row[i], row[i - 1], previousRow[i])
+    }
+  }
+
+  block (level, column, current, before, above) {
+    if (level < L.peak) return this.air()
+
+    const r = this.rand(level, column)
+    if (level < L.ground) return this.treeTop(r)
+    if (level < L.rock) return this.ground(r)
+    if (level < L.underground) return this.rock(r)
+    return this.underground(r, above, before, level - L.underground)
+  }
+
+  // always returns air
+  air () {
+    return T.air
+  }
+
+  // returns mostly air, but sometimes starts a tree
+  treeTop (r) {
+    if (r < P.tree) return T.wood
+    return T.air
+  }
+
+  // returns mostly soil and grass, sometimes gravel and sometimes air
+  ground (r) {
+    if (r < P.soil_gravel) return T.gravel
+    return T.soil
+  }
+
+  // returns mostly stones, sometimes gravel
+  rock (r) {
+    return r < P.rock_gravel ? T.gravel : T.stone
+  }
+
+  // return mostly bedrock, sometimes caves, depending on the level
+  underground (r, above, before, level) {
+    // the probability for a cave rises with the level
+    const a = P.cave / L.cave_max**2
+    const p = Math.min(P.cave, a * level**2)
+
+    if (r < p) return T.cave
+    return T.bedrock
+  }
+}
diff --git a/src/level/index.js b/src/level/index.js
new file mode 100644
index 0000000..2fa4322
--- /dev/null
+++ b/src/level/index.js
@@ -0,0 +1,39 @@
+import SeedRng from 'seedrandom'
+import FastSimplexNoise from 'fast-simplex-noise'
+
+import {type as T, level as L} from './def'
+import BlockGen from './first-iteration'
+import BlockExt from './second-iteration'
+
+export default class Level {
+  constructor (width, height, seed = 'super random seed') {
+    const random = SeedRng(seed)
+    const noiseGen = new FastSimplexNoise({ random })
+    this._x = 0
+    this._y = 0
+    this._w = width
+    this._h = height
+    this._grid = new Array(this._h)
+    this.blockGen = new BlockGen(noiseGen)
+    this.blockExt = new BlockExt(noiseGen)
+  }
+
+  grid (x, y) {
+    this._x = x
+    this._y = y
+
+    this.generate()
+    return this._grid
+  }
+
+  generate () {
+    for (let i = 0; i < this._h; i++) {
+      const level = this._y + i
+      const row = Array(this._w)
+      const previousRow = this._grid[i - 1] || Array()
+      this.blockGen.level(level, row, previousRow)
+      this.blockExt.level(level, row, previousRow)
+      this._grid[i] = row
+    }
+  }
+}
diff --git a/src/level/second-iteration.js b/src/level/second-iteration.js
new file mode 100644
index 0000000..55e91f0
--- /dev/null
+++ b/src/level/second-iteration.js
@@ -0,0 +1,46 @@
+import {type as T, level as L, probability as P} from './def'
+
+export default class BlockExt {
+  constructor (noiseGen) {
+    this.rand = (x, y) => 0.5 + 0.5 * noiseGen.raw2D(x, y)
+  }
+
+  level (level, row, previousRow) {
+    for (let i = 0; i < row.length; i++) {
+      const r = Math.abs(this.rand(level, i))
+
+      if (level < L.ground) this.trees(r, i, row, previousRow, level)
+      else if (level < L.rock) this.ground(r, i, row, previousRow)
+      else if (level < L.underground) this.rock(r, i, row, previousRow)
+      else this.underground(r, i, row, previousRow)
+    }
+  }
+
+  trees (r, i, row, previousRow, level) {
+    if (row[i] === T.wood && previousRow[i] === T.air) {
+      if (row[i - 1] === T.air) row[i - 1] = T.leaves
+      if (row[i + 1] === T.air) row[i + 1] = T.leaves
+      previousRow[i] = T.leaves
+    } else if (previousRow[i] === T.wood) {
+      row[i] = T.wood
+      if (row[i - 1] === T.wood) row[i - 1] = T.air
+    }
+  }
+
+  ground (r, i, row, previousRow) {
+    if (previousRow[i] === T.air) {
+      if (r < P.soil_hole) row[i] = T.air
+      if (row[i] === T.soil) row[i] = T.grass
+    } else if (previousRow[i] === T.wood && row[i - 1] === T.grass) {
+      row[i] = T.wood
+    }
+  }
+
+  rock (r, i, row, previousRow) {
+    if (previousRow[i] === T.soil && r < P.fray) row[i] = T.soil
+  }
+
+  underground (r, i, row, previousRow) {
+    if (previousRow[i] === T.stone && r < P.fray) row[i] = T.stone
+  }
+}
diff --git a/src/level/third-iteration.js b/src/level/third-iteration.js
new file mode 100644
index 0000000..e69de29
diff --git a/src/lib/block-generator.js b/src/lib/block-generator.js
deleted file mode 100644
index c215137..0000000
--- a/src/lib/block-generator.js
+++ /dev/null
@@ -1,57 +0,0 @@
-import SeedRng from 'seedrandom'
-import FastSimplexNoise from 'fast-simplex-noise'
-import * as T from './block-types'
-import * as P from './block-probabilities'
-import * as L from './block-levels'
-
-export default class BlockGen {
-  constructor (seed = 'so freakin random') {
-    const simplex = new FastSimplexNoise({ random: SeedRng(seed) })
-    this.rand = (x, y) => 0.5 + 0.5 * simplex.raw2D(x, y)
-  }
-
-  block (level, column, above, before) {
-    if (level < L.PEAK) return this.air()
-
-    const r = Math.abs(this.rand(level, column))
-    if (level < L.GROUND) return this.tree(r, above)
-    if (level < L.ROCK) return this.ground(r, above)
-    if (level < L.UNDERGROUND) return this.rock(r)
-    return this.underground(r, above, before, level - L.UNDERGROUND)
-  }
-
-  // always returns air
-  air () {
-    return T.AIR
-  }
-
-  // returns mostly air, but sometimes starts a tree
-  tree (r, above) {
-    const peak = above === T.AIR && r < P.TREE
-    if (peak || above === T.WOOD) return T.WOOD
-    return T.AIR
-  }
-
-  // returns mostly soil and grass, sometimes gravel and sometimes air
-  ground (r, above) {
-    if (above === T.AIR && r < P.SOIL_HOLE) return T.AIR
-    if (above === T.AIR) return T.GRASS
-    if (above === T.WOOD) return T.SOIL
-    return r < P.SOIL_GRAVEL ? T.GRAVEL : T.SOIL
-  }
-
-  // returns mostly stones, sometimes gravel
-  rock (r) {
-    return r < P.ROCK_GRAVEL ? T.GRAVEL : T.STONE
-  }
-
-  // return mostly bedrock, sometimes caves, depending on the level
-  underground (r, above, before, level) {
-    if (above === T.STONE || above === T.GRAVEL) return T.BEDROCK
-    const a = P.CAVE / P.CAVE_MAX**2
-    const p = Math.min(P.CAVE, a * level**2)
-
-    if (r < p) return T.CAVE
-    return T.BEDROCK
-  }
-}
diff --git a/src/lib/block-levels.js b/src/lib/block-levels.js
deleted file mode 100644
index 1a03f61..0000000
--- a/src/lib/block-levels.js
+++ /dev/null
@@ -1,4 +0,0 @@
-export const PEAK = 24
-export const GROUND = 28
-export const ROCK = 32
-export const UNDERGROUND = 48
diff --git a/src/lib/block-probabilities.js b/src/lib/block-probabilities.js
deleted file mode 100644
index 61bc0b7..0000000
--- a/src/lib/block-probabilities.js
+++ /dev/null
@@ -1,6 +0,0 @@
-export const TREE = 0.1
-export const SOIL_HOLE = 0.3
-export const SOIL_GRAVEL = 0.2
-export const ROCK_GRAVEL = 0.1
-export const CAVE = 0.5
-export const CAVE_MAX = 250
diff --git a/src/lib/block-types.js b/src/lib/block-types.js
deleted file mode 100644
index f8d13ed..0000000
--- a/src/lib/block-types.js
+++ /dev/null
@@ -1,9 +0,0 @@
-export const AIR = {type: 'air', hp: 0, damage: 0}
-export const GRASS = {type: 'grass', hp: 1, damage: 0}
-export const LEAVES = {type: 'leaves', hp: 1, damage: 0}
-export const WOOD = {type: 'wood', hp: 5, damage: 0}
-export const SOIL = {type: 'soil', hp: 2, damage: 0}
-export const GRAVEL = {type: 'gravel', hp: 5, damage: 0}
-export const STONE = {type: 'stone', hp: 10, damage: 0}
-export const BEDROCK = {type: 'bedrock', hp: 25, damage: 0}
-export const CAVE = {type: 'cave', hp: 0, damage: 0}
diff --git a/src/lib/level-generator.js b/src/lib/level-generator.js
deleted file mode 100644
index 95b977b..0000000
--- a/src/lib/level-generator.js
+++ /dev/null
@@ -1,55 +0,0 @@
-import * as T from './block-types'
-import * as L from './block-levels'
-import BlockGen from './block-generator'
-
-export default class Level {
-  constructor (width, height) {
-    this._x = 0
-    this._y = 0
-    this._w = width
-    this._h = height
-    this._grid = new Array(height)
-    this.blockGen = new BlockGen('super random seed')
-  }
-
-  grid (x, y) {
-    this._x = x
-    this._y = y
-    this.generate()
-    return this._grid
-  }
-
-  generate () {
-    // TODO: caching
-    for (let i = 0; i < this._h; i++) {
-      this._grid[i] = this._row(i + this._y)
-    }
-  }
-
-  _row (level = 0) {
-    const row = Array(this._w)
-    const previousRow = this._grid[level - 1] || Array()
-
-    // first step: generate a row for the given level
-    for (let i = 0; i < row.length; i++) {
-      const above = previousRow[i]
-      row[i] = this.blockGen.block(level, i, above, row[i - 1])
-    }
-
-    // second step: add extras like tree leaves
-    if (level < L.GROUND && level > L.PEAK) {
-      for (let i = 0; i < row.length; i++) {
-        const above = previousRow[i]
-        const block = row[i]
-
-        if (block === T.WOOD && above === T.AIR) {
-          if (row[i - 1] === T.AIR) row[i - 1] = T.LEAVES
-          if (row[i + 1] === T.AIR) row[i + 1] = T.LEAVES
-          previousRow[i] = T.LEAVES
-        }
-      }
-    }
-
-    return row
-  }
-}