diff --git a/CMakeLists.txt b/CMakeLists.txt
index f2c6eb7..217e8c9 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,6 +24,7 @@ add_executable(PixelDefense
         game/pathfinding.h
         game/systems.h
         game/systems_entity.c
+        game/systems_input.c
         game/systems_ui.c
 )
 
diff --git a/game/game_state.h b/game/game_state.h
index a76c724..04dc92c 100644
--- a/game/game_state.h
+++ b/game/game_state.h
@@ -19,7 +19,7 @@ typedef struct InputState {
     MouseButton RMB;
     MouseButton MMB;
     KeyboardKey ESC;
-    f32 DRAG_LIMIT;
+    f32 CLICK_LIMIT;
     // Common
     Vector2 mouseDown;
     Vector2 mouseDownWorld;
@@ -30,7 +30,8 @@ typedef struct InputState {
     TilePosition buildingPos;
     TileSize buildingSize;
     // SELECTED_UNITS
-    // SELECTED_OBJECTS
+    ecs_entity_t *entities;
+    // SELECTED_OBJECT
     // SELECTED_BUILDING
 } InputState;
 
@@ -43,7 +44,6 @@ typedef struct Game {
     BzSpatialGrid *entityGrid;
     f32 frameDuration;
     ecs_entity_t entity;
-    InputState input;
     struct {
         i64 wood;
         i64 iron;
@@ -66,5 +66,6 @@ typedef struct Game {
 extern ecs_world_t *ECS;
 
 extern ECS_COMPONENT_DECLARE(Game);
+extern ECS_COMPONENT_DECLARE(InputState);
 
 #endif //PIXELDEFENSE_GAME_STATE_H
diff --git a/game/main.c b/game/main.c
index 2167b69..272fb7f 100644
--- a/game/main.c
+++ b/game/main.c
@@ -14,6 +14,7 @@
 #include <raymath.h>
 
 ECS_COMPONENT_DECLARE(Game);
+ECS_COMPONENT_DECLARE(InputState);
 
 ecs_world_t *ECS = NULL;
 
@@ -50,21 +51,27 @@ bool init(void *userData) {
 
     ECS = ecs_init();
 
-    ECS_COMPONENT_DEFINE(ECS, Game);
     initComponentIDs(ECS);
 
     // For ecs explorer
     //ecs_singleton_set(ECS, EcsRest, {0});
     //ECS_IMPORT(ECS, FlecsMonitor);
 
+    ECS_COMPONENT_DEFINE(ECS, Game);
     ecs_singleton_set(ECS, Game, {});
     Game *game = ecs_singleton_get_mut(ECS, Game);
 
-    game->input.LMB = MOUSE_LEFT_BUTTON;
-    game->input.RMB = MOUSE_RIGHT_BUTTON;
-    game->input.MMB = MOUSE_MIDDLE_BUTTON;
+    ECS_COMPONENT_DEFINE(ECS, InputState);
+    ecs_singleton_set(ECS, InputState, {});
+    InputState *input = ecs_singleton_get_mut(ECS, InputState);
 
-    game->input.ESC = KEY_ESCAPE;
+    input->LMB = MOUSE_LEFT_BUTTON;
+    input->RMB = MOUSE_RIGHT_BUTTON;
+    input->MMB = MOUSE_MIDDLE_BUTTON;
+    input->ESC = KEY_ESCAPE;
+    input->CLICK_LIMIT = 0.2f;
+
+    input->entities = bzArrayCreate(ecs_entity_t, 16);
 
 
     // init pools
@@ -156,6 +163,7 @@ bool init(void *userData) {
 void deinit(void *userData) {
     BZ_UNUSED(userData);
     Game *game = ecs_singleton_get_mut(ECS, Game);
+    InputState *input = ecs_singleton_get_mut(ECS, InputState);
 
     bzTileMapDestroy(&game->map);
     bzTilesetDestroy(&game->terrainTileset);
@@ -163,10 +171,12 @@ void deinit(void *userData) {
     bzTilesetDestroy(&game->entitiesTileset);
 
     Game gameCopy = *game;
+    InputState inputCopy = *input;
 
     ecs_fini(ECS);
     ECS = NULL;
 
+    bzArrayDestroy(inputCopy.entities);
     bzObjectPoolDestroy(gameCopy.pools.pathData);
     bzSpatialGridDestroy(gameCopy.entityGrid);
 }
@@ -174,74 +184,12 @@ void deinit(void *userData) {
 
 void update(float dt, void *userData) {
     BZ_UNUSED(userData);
-    Game *game = ecs_singleton_get_mut(ECS, Game);
 
     char titleBuf[32];
     snprintf(titleBuf, sizeof(titleBuf), "FPS: %d | %.2f ms", GetFPS(), GetFrameTime() * 1000);
     SetWindowTitle(titleBuf);
 
-    ImGuiIO *io = igGetIO();
-    if (io->WantCaptureMouse || io->WantCaptureKeyboard)
-        return;
-
-    if (IsKeyDown(KEY_W)) game->camera.target.y -= 20;
-    if (IsKeyDown(KEY_S)) game->camera.target.y += 20;
-    if (IsKeyDown(KEY_A)) game->camera.target.x -= 20;
-    if (IsKeyDown(KEY_D)) game->camera.target.x += 20;
-
-    if (IsKeyDown(KEY_Q)) game->camera.rotation--;
-    if (IsKeyDown(KEY_E)) game->camera.rotation++;
-
-
-    game->camera.zoom += ((float) GetMouseWheelMove() * 0.05f);
-    BzTileMap *map = &game->map;
-
-    InputState *input = &game->input;
-    if (IsMouseButtonPressed(input->LMB)) {
-        game->input.mouseDown = GetMousePosition();
-        game->input.mouseDownWorld = GetScreenToWorld2D(game->input.mouseDown, game->camera);
-        game->input.mouseDownElapsed = 0;
-    } else if (IsMouseButtonDown(input->LMB)) {
-        game->input.mouseDownElapsed += dt;
-    }
-
-    switch (input->state) {
-        case INPUT_NONE:
-            if (IsMouseButtonUp(input->LMB)) {
-
-            }
-            break;
-        case INPUT_BUILDING:
-            if (IsKeyPressed(input->ESC) ||
-                IsMouseButtonPressed(input->RMB) ||
-                input->building == 0) {
-                input->state = INPUT_NONE;
-                input->building = 0;
-                break;
-            }
-            Vector2 worldPos = GetScreenToWorld2D(GetMousePosition(), game->camera);
-            int tileX = (int) worldPos.x / map->tileWidth;
-            int tileY = (int) worldPos.y / map->tileHeight;
-            BZ_ASSERT(input->building);
-            BzTile sizeX = 0, sizeY = 0;
-            getBuildingSize(input->building, &sizeX, &sizeY);
-            bool canPlace = canPlaceBuilding(&game->map, input->building, tileX, tileY);
-            if (canPlace && IsMouseButtonDown(input->LMB)) {
-                placeBuilding(&game->map, input->building, tileX, tileY);
-            }
-            input->buildingCanPlace = canPlace;
-            input->buildingPos = (TilePosition) {tileX, tileY};
-            input->buildingSize = (TileSize) {sizeX, sizeY};
-            break;
-        case INPUT_SELECTED_UNITS:
-            break;
-        case INPUT_SELECTED_OBJECT:
-            break;
-        case INPUT_SELECTED_BUILDING:
-            break;
-    }
-
-
+   updatePlayerInput(NULL);
 }
 
 static bool isUnitObstructed(f32 x, f32 y, BzTileMap *map) {
@@ -299,27 +247,44 @@ static void placeUnits(i32 numUnits, f32 unitSpacing, Vector2 start, Vector2 end
 void render(float dt, void *userData) {
     BZ_UNUSED(userData);
     Game *game = ecs_singleton_get_mut(ECS, Game);
+    InputState *input = ecs_singleton_get_mut(ECS, InputState);
 
     ClearBackground(RAYWHITE);
     BeginMode2D(game->camera);
 
     bzTileMapDraw(&game->map);
 
-    InputState *input = &game->input;
+    Vector2 worldPos = GetScreenToWorld2D(GetMousePosition(), game->camera);
     switch (input->state) {
         case INPUT_NONE:
+            if (IsMouseButtonDown(input->LMB) && input->mouseDownElapsed > input->CLICK_LIMIT) {
+                Vector2 start = input->mouseDownWorld;
+                Vector2 end = worldPos;
+                if (start.x > end.x) {
+                    f32 tmp = start.x;
+                    start.x = end.x;
+                    end.x = tmp;
+                }
+                if (start.y > end.y) {
+                    f32 tmp = start.y;
+                    start.y = end.y;
+                    end.y = tmp;
+                }
+                Rectangle area = {start.x, start.y, end.x - start.x, end.y - start.y};
+                DrawRectangleLines(area.x, area.y, area.width, area.height, RED);
+            }
             break;
         case INPUT_BUILDING: {
-            Color placeColor = game->input.buildingCanPlace ?
+            Color placeColor = input->buildingCanPlace ?
                                (Color) {0, 255, 0, 200} :
                                (Color) {255, 0, 0, 200};
 
             BzTile width = game->map.tileWidth;
             BzTile height = game->map.tileHeight;
-            DrawRectangleLines(game->input.buildingPos.x * width,
-                               game->input.buildingPos.y * height,
-                               game->input.buildingSize.sizeX * width,
-                               game->input.buildingSize.sizeY * height, placeColor);
+            DrawRectangleLines(input->buildingPos.x * width,
+                               input->buildingPos.y * height,
+                               input->buildingSize.sizeX * width,
+                               input->buildingSize.sizeY * height, placeColor);
             break;
         }
         case INPUT_SELECTED_UNITS:
@@ -414,11 +379,12 @@ void render(float dt, void *userData) {
 void imguiRender(float dt, void *userData) {
     BZ_UNUSED(userData);
     Game *game = ecs_singleton_get_mut(ECS, Game);
+    InputState *input = ecs_singleton_get_mut(ECS, InputState);
 
     igSetNextWindowSize((ImVec2){300, 400}, ImGuiCond_FirstUseEver);
     igBegin("Debug Menu", NULL, 0);
     const char *inputState = "NONE";
-    switch (game->input.state) {
+    switch (input->state) {
         case INPUT_NONE:
             inputState = "NONE";
             break;
@@ -437,6 +403,21 @@ void imguiRender(float dt, void *userData) {
     }
     igText("Input state: %s", inputState);
     if (igCollapsingHeader_TreeNodeFlags("Selection", 0)) {
+        switch (input->state) {
+            case INPUT_SELECTED_UNITS:
+                igText("Selected units:");
+                for (i32 i = 0; i < bzArraySize(input->entities); i++) {
+                    igText("\t%llu", bzArrayGet(input->entities, i));
+                }
+                break;
+            case INPUT_SELECTED_OBJECT:
+                break;
+            case INPUT_SELECTED_BUILDING:
+                break;
+            default:
+                igText("NONE");
+                break;
+        }
 
     }
     if (igCollapsingHeader_TreeNodeFlags("Resources", 0)) {
@@ -448,11 +429,11 @@ void imguiRender(float dt, void *userData) {
     }
     if (igCollapsingHeader_TreeNodeFlags("BuildMenu", 0)) {
         for (int i = 0; i < BUILDINGS_COUNT; i++) {
-            if (igSelectable_Bool(getBuildingStr(i), game->input.building == i, 0, (ImVec2){0, 0}))
-                game->input.building = i;
+            if (igSelectable_Bool(getBuildingStr(i), input->building == i, 0, (ImVec2){0, 0}))
+                input->building = i;
         }
-        if (game->input.building)
-            game->input.state = INPUT_BUILDING;
+        if (input->building)
+            input->state = INPUT_BUILDING;
 
     }
     if (igCollapsingHeader_TreeNodeFlags("DebugDraw", 0)) {
diff --git a/game/systems.h b/game/systems.h
index faa90bc..0c90ff6 100644
--- a/game/systems.h
+++ b/game/systems.h
@@ -70,4 +70,17 @@ void renderColliders(ecs_iter_t *it);
  */
 void renderDebugPath(ecs_iter_t *it);
 
+
+
+/**********************************
+ * Entity Systems
+ **********************************/
+
+/*
+ * Task:
+ * 0: Game (singleton)
+ * 0: InputState (singleton)
+ */
+void updatePlayerInput(ecs_iter_t *it);
+
 #endif //PIXELDEFENSE_SYSTEMS_H
diff --git a/game/systems_input.c b/game/systems_input.c
new file mode 100644
index 0000000..fe0f0f6
--- /dev/null
+++ b/game/systems_input.c
@@ -0,0 +1,202 @@
+#include "systems.h"
+#include "game_state.h"
+#include "buildings.h"
+#include "pathfinding.h"
+#include <rlImGui.h>
+#include <raymath.h>
+
+void pickEntity(BzSpatialGrid *entityGrid, Vector2 point, ecs_entity_t **outEntities);
+void pickEntities(BzSpatialGrid *entityGrid, Rectangle area, ecs_entity_t **outEntities);
+
+void updatePlayerInput(ecs_iter_t *it) {
+    f32 dt = GetFrameTime();
+    ImGuiIO *io = igGetIO();
+    if (io->WantCaptureMouse || io->WantCaptureKeyboard)
+        return;
+
+    Game *game = ecs_singleton_get_mut(ECS, Game);
+    InputState *input = ecs_singleton_get_mut(ECS, InputState);
+    if (IsKeyDown(KEY_W)) game->camera.target.y -= 20;
+    if (IsKeyDown(KEY_S)) game->camera.target.y += 20;
+    if (IsKeyDown(KEY_A)) game->camera.target.x -= 20;
+    if (IsKeyDown(KEY_D)) game->camera.target.x += 20;
+
+    if (IsKeyDown(KEY_Q)) game->camera.rotation--;
+    if (IsKeyDown(KEY_E)) game->camera.rotation++;
+
+
+    game->camera.zoom += ((float) GetMouseWheelMove() * 0.05f);
+    BzTileMap *map = &game->map;
+
+    if (IsMouseButtonPressed(input->LMB)) {
+        input->mouseDown = GetMousePosition();
+        input->mouseDownWorld = GetScreenToWorld2D(input->mouseDown, game->camera);
+        input->mouseDownElapsed = 0;
+    } else if (IsMouseButtonDown(input->LMB)) {
+        input->mouseDownElapsed += dt;
+    }
+
+    Vector2 worldPos = GetScreenToWorld2D(GetMousePosition(), game->camera);
+    int tileX = (int) worldPos.x / map->tileWidth;
+    int tileY = (int) worldPos.y / map->tileHeight;
+    switch (input->state) {
+        case INPUT_NONE:
+            if (IsMouseButtonReleased(input->LMB) && input->mouseDownElapsed > input->CLICK_LIMIT) {
+                // Dragging
+
+                Vector2 start = input->mouseDownWorld;
+                Vector2 end = worldPos;
+                if (start.x > end.x) {
+                    f32 tmp = start.x;
+                    start.x = end.x;
+                    end.x = tmp;
+                }
+                if (start.y > end.y) {
+                    f32 tmp = start.y;
+                    start.y = end.y;
+                    end.y = tmp;
+                }
+                Rectangle pickArea = {start.x, start.y, end.x - start.x, end.y - start.y};
+
+                pickEntities(game->entityGrid, pickArea, &input->entities);
+                if (bzArraySize(input->entities) > 0) {
+                    input->state = INPUT_SELECTED_UNITS;
+                    break;
+                }
+
+            } else if (IsMouseButtonReleased(input->LMB)) {
+                // Click
+
+                // 1. Entity
+                pickEntity(game->entityGrid, worldPos, &input->entities);
+                if (bzArraySize(input->entities) > 0) {
+                    input->state = INPUT_SELECTED_UNITS;
+                    break;
+                }
+
+                // 2. Object
+
+                // 3. Building
+            }
+            break;
+        case INPUT_BUILDING:
+            if (IsKeyPressed(input->ESC) ||
+                IsMouseButtonPressed(input->RMB) ||
+                input->building == 0) {
+                input->state = INPUT_NONE;
+                input->building = 0;
+                break;
+            }
+            BZ_ASSERT(input->building);
+            BzTile sizeX = 0, sizeY = 0;
+            getBuildingSize(input->building, &sizeX, &sizeY);
+            bool canPlace = canPlaceBuilding(&game->map, input->building, tileX, tileY);
+            if (canPlace && IsMouseButtonDown(input->LMB)) {
+                placeBuilding(&game->map, input->building, tileX, tileY);
+            }
+            input->buildingCanPlace = canPlace;
+            input->buildingPos = (TilePosition) {tileX, tileY};
+            input->buildingSize = (TileSize) {sizeX, sizeY};
+            break;
+        case INPUT_SELECTED_UNITS:
+            if (IsKeyPressed(input->ESC)) {
+                input->state = INPUT_NONE;
+                break;
+            }
+            if (IsMouseButtonPressed(input->LMB)) {
+                bzArrayFor(input->entities, i) {
+                    ecs_entity_t entity = bzArrayGet(input->entities, i);
+                    ecs_remove(ECS, entity, Path);
+
+                    const Position *start = ecs_get(ECS, entity, Position);
+                    Path path = {NULL, 0};
+                    findPath(&(PathfindingDesc) {
+                        .start=(TilePosition) {
+                                start->x / game->map.tileWidth,
+                                start->y / game->map.tileHeight,
+                        },
+                        .target=(TilePosition) {tileX, tileY},
+                        .map=&game->map,
+                        .outPath=&path,
+                        .pool=game->pools.pathData
+                    });
+                    if (!path.paths) continue;
+                    ecs_set_ptr(ECS, entity, Path, &path);
+                    input->state = INPUT_NONE;
+                }
+
+            }
+            break;
+        case INPUT_SELECTED_OBJECT:
+            break;
+        case INPUT_SELECTED_BUILDING:
+            break;
+    }
+}
+
+static bool getEntityBounds(ecs_entity_t entity, Position *outPos, Size *outSize,
+                            Rectangle *outBounds) {
+    if (!ecs_is_alive(ECS, entity))
+        return false;
+    const Position *pos = ecs_get(ECS, entity, Position);
+    if (!pos)
+        return false;
+    const Size *size = ecs_get(ECS, entity, Size);
+    if (!size)
+        return false;
+
+    if (outPos) {
+        *outPos = *pos;
+    }
+    if (outSize) {
+        *outSize = *size;
+    }
+    if (outBounds) {
+        *outBounds = (Rectangle) {
+                pos->x - size->x * 0.5f,
+                pos->y - size->y * 0.5f,
+                size->x, size->y
+        };
+    }
+    return true;
+}
+
+void pickEntity(BzSpatialGrid *entityGrid, Vector2 point, ecs_entity_t **outEntities) {
+    BZ_ASSERT(*outEntities);
+    bzArrayClear(*outEntities);
+    BzSpatialGridIter it = bzSpatialGridIter(entityGrid, point.x, point.y, 0.0f, 0.0f);
+    f32 closestDst = INFINITY;
+    ecs_entity_t closest = 0;
+    while (bzSpatialGridQueryNext(&it)) {
+        ecs_entity_t entity = *(ecs_entity_t *) it.data;
+        Vector2 pos;
+        Rectangle bounds;
+        if (!getEntityBounds(entity, &pos, NULL, &bounds)) continue;
+
+        if (!CheckCollisionPointRec(point, bounds)) continue;
+
+        f32 curDst = Vector2Distance(point, pos);
+        if (closestDst > curDst) {
+            closestDst = curDst;
+            closest = entity;
+        }
+    }
+    if (closest) {
+        bzArrayPush(*outEntities, closest);
+    }
+}
+
+void pickEntities(BzSpatialGrid *entityGrid, Rectangle area, ecs_entity_t **outEntities) {
+    BZ_ASSERT(*outEntities);
+    bzArrayClear(*outEntities);
+
+    BzSpatialGridIter it = bzSpatialGridIter(entityGrid, area.x, area.y, area.width, area.height);
+    while (bzSpatialGridQueryNext(&it)) {
+        ecs_entity_t entity = *(ecs_entity_t *) it.data;
+        Rectangle bounds;
+        if (!getEntityBounds(entity, NULL, NULL, &bounds)) continue;
+
+        if (!CheckCollisionRecs(area, bounds)) continue;
+        bzArrayPush(*outEntities, entity);
+    }
+}