diff --git a/ClassCreep.js b/ClassCreep.js
index d55fa60..50c54cd 100644
--- a/ClassCreep.js
+++ b/ClassCreep.js
@@ -1,23 +1,19 @@
+// Replace creep class with _creep class
 module.exports = {
 	setup: function () { Creep.prototype = _Creep.prototype; }
 }
 
 class _Creep extends Creep {
+
 	init() {
+		// if no role is assigned become harvester
 		if (this.memory.role == undefined) this.memory.role = ROLE_HARVESTER;
-		if (this.memory.recharge == undefined) this.memory.recharge = true;
-	}
-
-	toggleChargeMode() {
-		if (this.store.getFreeCapacity(RESOURCE_ENERGY) == 0) {
-			this.memory.recharge = false;
-		} else if (this.store.getUsedCapacity(RESOURCE_ENERGY) == 0) {
-			this.memory.recharge = true;
-		} else return;
-		this.memory.target = undefined;
-		this.memory.path = undefined;
+		// start by gathering new energy 
+		if (this.memory.gathering == undefined) this.memory.gathering = true;
+		this.memory.init = true;
 	}
 
+	//#region Target detection
 	findTarget(TARGET) {
 		if (this.memory.target == undefined) {
 			const target = this.pos.findClosestByPath(TARGET);
@@ -36,26 +32,30 @@ class _Creep extends Creep {
 		return OK;
 	}
 
+	findBestTarget(TARGET, sort) {
+		if (this.memory.target == undefined) {
+			const targets = this.room.find(TARGET);
+			const target = targets.sort(sort).shift();
+			if (target == null) return ERR_NOT_FOUND;
+			else this.memory.target = target.id;
+		}
+		return OK;
+	}
+	//#endregion
+
+	//#region Gathering
 	harvestSource() {
-		if (this.findTarget(FIND_SOURCES, {
-			filter: (s) => {
-				const area = s.room.lookAtArea(s.pos.y - 1, s.pos.x - 1, s.pos.y + 1, s.pos.y + 1, true);
-				var free_space = 0;
-				area.forEach(entry => {
-					if (entry.type == "creep") free_space--;
-					else if (entry.type == "terrain" && entry.terrain == "plain") free_space++;
-					else if (entry.type == "terrain" && entry.terrain == "swamp") free_space++;
-				});
-				return free_space > 0;
-			}
-		}) == ERR_NOT_FOUND) return;
+		// search for source with highest energy level.
+		if (this.findBestTarget(FIND_SOURCES, function (s1, s2) { return s2.energy - s1.energy }) == ERR_NOT_FOUND) return;
 		const target = Game.getObjectById(this.memory.target);
 		if (this.moveToTarget() == OK) {
 			this.harvest(target);
 			this.toggleChargeMode();
 		}
 	}
+	//#endregion
 
+	//#region Roles
 	harvesterJobs() {
 		if (this.memory.counter == undefined) this.memory.counter = 0;
 		switch (this.memory.counter % 4) {
@@ -85,6 +85,11 @@ class _Creep extends Creep {
 			}
 		}) == ERR_NOT_FOUND) return;
 		const target = Game.getObjectById(this.memory.target);
+		if (target.store.getFreeCapacity(RESOURCE_ENERGY) == 0) {
+			this.memory.target = undefined;
+			this.supplyStructures();
+			return;
+		}
 		if (this.moveToTarget() == OK) {
 			this.transfer(target, RESOURCE_ENERGY);
 			this.toggleChargeMode();
@@ -100,56 +105,100 @@ class _Creep extends Creep {
 	}
 
 	repairStructures() {
-		if (this.findTarget(FIND_MY_STRUCTURES, {
+		this.findTarget(FIND_MY_STRUCTURES, {
 			filter: (s) => {
 				return s.hits < s.hitsMax &&
 					s.structureType != STRUCTURE_WALL &&
 					s.structureType != STRUCTURE_RAMPART;
 			}
-		}) == ERR_NOT_FOUND);
+		});
 		if (this.findTarget(FIND_MY_STRUCTURES, {
 			filter: (s) => {
 				return s.hits < s.hitsMax;
 			}
 		}) == ERR_NOT_FOUND) return;
-
-		const target = Game.getObjectById(this.memory.target.id);
+		const target = Game.getObjectById(this.memory.target);
+		if (target.hits == target.hitsMax) {
+			this.memory.target = undefined;
+			this.repairStructures();
+			return;
+		}
 		if (this.moveToTarget() == OK) {
-			this.repair(target);
+			if (this.repair(target) == OK) return;
 			this.toggleChargeMode();
 		}
 	}
 
 	buildConstructionSites() {
 		if (this.findTarget(FIND_MY_CONSTRUCTION_SITES) == ERR_NOT_FOUND) return;
-		const target = Game.getObjectById(this.memory.target.id);
+		const target = Game.getObjectById(this.memory.target);
+		if (target == null) {
+			this.memory.target = undefined;
+			this.buildConstructionSites();
+			return;
+		}
 		if (this.moveToTarget() == OK) {
-			this.build(target);
+			if (this.build(target) == OK) return;
 			this.toggleChargeMode();
 		}
 	}
+	//#endregion
 
+	//#region State
+	toggleChargeMode() {
+		if (this.store.getFreeCapacity(RESOURCE_ENERGY) == 0) {
+			this.memory.gathering = false;
+		} else if (this.store.getUsedCapacity(RESOURCE_ENERGY) == 0) {
+			this.memory.gathering = true;
+		} else return;
+		this.memory.target = undefined;
+		this.memory.path = undefined;
+	}
+	//#endregion
+
+	//#region Movement
 	moveToTarget() {
+		// Memory allocation
+		if (this.memory.move == undefined) this.memory.move = {};
+
+		// Get target to walk to.
 		const target = Game.getObjectById(this.memory.target)
+		if (target == null) return ERR_INVALID_TARGET;
+
+		// Check if arrived at target.
 		if (this.pos.inRangeTo(target.pos.x, target.pos.y, 1)) {
-			this.memory.path = undefined;
+			this.memory.move.path = undefined;
 			return OK;
 		}
-		if (this.pos.inRangeTo(target.pos.x, target.pos.y, 5)) {
-			this.moveTo(target)
-			return ERR_BUSY;
+
+		// Check if in locked position every 5 ticks
+		if (this.memory.move.last_pos == undefined) this.memory.move.last_pos = this.pos;
+		if (this.ticksToLive % 5 == 0) {
+			if (this.memory.move.last_pos.x == this.pos.x &&
+				this.memory.move.last_pos.y == this.pos.y) {
+				this.moveTo(target);
+				this.memory.move.path = undefined;
+				return ERR_BUSY;
+			}
+			this.memory.move.last_pos = this.pos;
 		}
-		if (this.memory.path == undefined) {
-			this.memory.path = this.pos.findPathTo(target.pos, {
+
+		// Check if a new path is required.
+		if (this.memory.move.path == undefined) {
+			this.memory.move.path = this.pos.findPathTo(target.pos, {
 				ignoreCreeps: true, range: 1
 			});
 		}
-		const response = this.moveByPath(this.memory.path);
+
+		// Perform move
+		const response = this.moveByPath(this.memory.move.path);
 		if (response == OK) return ERR_BUSY;
+		// If error occurs remove path and use moveTo to move. 
 		if (response == ERR_INVALID_ARGS || response == ERR_NOT_FOUND) {
 			this.moveTo(target);
-			this.memory.path = undefined;
+			this.memory.move.path = undefined;
 			return ERR_BUSY;
 		}
 	}
+	//#endregion
 }
diff --git a/ClassRoom.js b/ClassRoom.js
index 15b2020..5881b09 100644
--- a/ClassRoom.js
+++ b/ClassRoom.js
@@ -73,7 +73,7 @@ class _Room extends Room {
 	}
 
 	planStructures() {
-
+		this.memory.roadsPlanned = false;
 	}
 
 	//#endregion
diff --git a/_creeps.js b/_creeps.js
index ad19946..199c2d5 100644
--- a/_creeps.js
+++ b/_creeps.js
@@ -17,9 +17,10 @@ module.exports = {
 				delete Memory.creeps[creep_name];
 				return;
 			}
+			if (creep.memory.init == undefined) creep.init();
 			switch (creep.memory.role) {
 				case ROLE_HARVESTER:
-					if (creep.memory.recharge) creep.harvestSource();
+					if (creep.memory.gathering) creep.harvestSource();
 					else creep.harvesterJobs();
 					break;
 				default:
diff --git a/_rooms.js b/_rooms.js
index 3b55701..94b8695 100644
--- a/_rooms.js
+++ b/_rooms.js
@@ -9,7 +9,7 @@ module.exports = {
 	update: function () {
 		for (const room_name in Game.rooms) {
 			const room = Game.rooms[room_name];
-			if (Game.time % 1000 == 0) {
+			if (Game.time % 100 == 0) {
 				// Place new building types if the max construcion sites isn't achieved yet.
 				if (room.canConstruct()) {
 					room.planRoads();