diff --git a/source/engine/2dphysics.c b/source/engine/2dphysics.c
index 9b04785..10459f4 100644
--- a/source/engine/2dphysics.c
+++ b/source/engine/2dphysics.c
@@ -19,9 +19,14 @@ float phys2d_gravity = -50.f;
 void phys2d_init()
 {
     space = cpSpaceNew();
+    phys2d_set_gravity(0, phys2d_gravity);
     cpSpaceSetGravity(space, cpv(0, phys2d_gravity));
 }
 
+void phys2d_set_gravity(float x, float y) {
+    cpSpaceSetGravity(space, cpv(x, y));
+}
+
 void phys2d_update(float deltaT)
 {
     cpSpaceStep(space, deltaT);
@@ -29,7 +34,7 @@ void phys2d_update(float deltaT)
 
 void phys2d_apply()
 {
-    cpSpaceSetGravity(space, cpv(0, phys2d_gravity));
+    phys2d_set_gravity(0, phys2d_gravity);
 }
 
 void phys2d_shape_apply(struct phys2d_shape *shape)
@@ -42,7 +47,6 @@ void init_phys2dshape(struct phys2d_shape *shape, struct gameobject *go)
 {
     shape->go = go;
     cpShapeSetCollisionType(shape->shape, go);
-    YughInfo("Added shape type %d", go);
     phys2d_shape_apply(shape);
 }
 
@@ -58,7 +62,6 @@ struct phys2d_circle *Make2DCircle(struct gameobject *go)
     new->radius = 10.f;
     new->offset[0] = 0.f;
     new->offset[1] = 0.f;
-    phys2d_circleinit(new, go);
 
     return new;
 }
@@ -100,7 +103,7 @@ struct phys2d_segment *Make2DSegment(struct gameobject *go)
     new->a[1] = 0.f;
     new->b[0] = 0.f;
     new->b[1] = 0.f;
-    phys2d_seginit(new, go);
+
 
     return new;
 }
@@ -134,8 +137,6 @@ struct phys2d_box *Make2DBox(struct gameobject *go)
     new->offset[0] = 0.f;
     new->offset[1] = 0.f;
 
-    phys2d_boxinit(new, go);
-
     return new;
 }
 
@@ -169,8 +170,6 @@ struct phys2d_poly *Make2DPoly(struct gameobject *go)
     new->points = NULL;
     new->radius = 0.f;
 
-    phys2d_polyinit(new, go);
-
     return new;
 }
 
@@ -220,8 +219,6 @@ struct phys2d_edge *Make2DEdge(struct gameobject *go)
     new->thickness = 0.f;
     new->shapes = malloc(sizeof(cpShape *));
 
-    phys2d_edgeinit(new, go);
-
     return new;
 }
 
@@ -458,8 +455,6 @@ static cpBool s7_phys_cb_begin(cpArbiter *arb, cpSpace *space, void *data) {
     struct gameobject *go = data;
     script_call_sym(go->cbs->begin);
 
-    YughInfo("Gameobject %p began collision.", data);
-
     cpBody *body1;
     cpBody *body2;
     cpArbiterGetBodies(arb, &body1, &body2);
@@ -468,8 +463,6 @@ static cpBool s7_phys_cb_begin(cpArbiter *arb, cpSpace *space, void *data) {
     cpShape *shape2;
     cpArbiterGetShapes(arb, &shape1, &shape2);
 
-    YughInfo("Body %p began collision with body %p.", body1, body2);
-    YughInfo("Shape %p began collision with shape %p.", shape1, shape2);
     return 1;
 }
 
@@ -493,7 +486,6 @@ void phys2d_add_handler_type(int cmd, struct gameobject *go, s7_pointer cb) {
         go->cbs = malloc(sizeof(*go->cbs));
 
     handler->userData = go;
-    YughInfo("Making phys handler %d for type %d", cmd, go);
 
     switch (cmd) {
         case 0:
diff --git a/source/engine/2dphysics.h b/source/engine/2dphysics.h
index e1db0c3..184a89a 100644
--- a/source/engine/2dphysics.h
+++ b/source/engine/2dphysics.h
@@ -101,6 +101,7 @@ void phys2d_update(float deltaT);
 void phys2d_apply();
 
 void phys2d_add_handler_type(int cmd, struct gameobject *go,  s7_pointer cb);
+void phys2d_set_gravity(float x, float y);
 
 void shape_gui(struct phys2d_shape *shape);
 
diff --git a/source/engine/editor/editorstate.h b/source/engine/editor/editorstate.h
index 261d504..bb23f7c 100644
--- a/source/engine/editor/editorstate.h
+++ b/source/engine/editor/editorstate.h
@@ -7,4 +7,6 @@ extern void (*asset_command)(char *asset);
 
 void print_file(char *file);
 
+
+
 #endif
diff --git a/source/engine/gameobject.c b/source/engine/gameobject.c
index 36b4686..60083ac 100644
--- a/source/engine/gameobject.c
+++ b/source/engine/gameobject.c
@@ -145,6 +145,7 @@ int gameobject_makefromprefab(char *path)
 void gameobject_init(struct gameobject *go, FILE * fprefab)
 {
     go->body = cpSpaceAddBody(space, cpBodyNew(go->mass, 1.f));
+    cpBodySetType(go->body, go->bodytype);
 
     int comp_n;
     fread(&comp_n, sizeof(int), 1, fprefab);
@@ -165,6 +166,8 @@ void gameobject_init(struct gameobject *go, FILE * fprefab)
 
         newc->init(newc->data, go);
     }
+
+
 }
 
 void gameobject_saveprefab(struct gameobject *go)
diff --git a/source/engine/mrbffi.c b/source/engine/mrbffi.c
index a8f7dfd..7a69042 100644
--- a/source/engine/mrbffi.c
+++ b/source/engine/mrbffi.c
@@ -12,6 +12,9 @@
 #include "input.h"
 #include "gameobject.h"
 #include "openglrender.h"
+#include "2dphysics.h"
+
+#include "yugine.h"
 
 #include "s7.h"
 
@@ -176,6 +179,29 @@ s7_pointer s7_sys_cmd(s7_scheme *sc, s7_pointer args) {
         case 0:
             quit();
             break;
+
+        case 1:
+            sim_start();
+            break;
+
+        case 2:
+            sim_stop();
+            break;
+
+        case 3:
+            sim_pause();
+            break;
+
+        case 4:
+            sim_step();
+            break;
+
+        case 5:
+            return s7_make_boolean(sc, sim_playing());
+
+        case 6:
+            return s7_make_boolean(sc, sim_paused());
+
     }
 
     return args;
@@ -291,6 +317,26 @@ s7_pointer s7_phys_cmd(s7_scheme *sc, s7_pointer args) {
     phys2d_add_handler_type(cmd, get_gameobject_from_id(go), env);
 }
 
+/* Query physics bodies */
+s7_pointer s7_phys_q(s7_scheme *sc, s7_pointer args) {
+    struct gameobject * go = get_gameobject_from_id(s7_integer(s7_car(args)));
+    int q = s7_integer(s7_cadr(args));
+
+    switch(q) {
+        case 0:
+            return s7_make_integer(sc, cpBodyGetType(go->body));
+
+    }
+}
+
+s7_pointer s7_phys_set(s7_scheme *sc, s7_pointer args) {
+    int cmd = s7_integer(s7_car(args));
+    double x = s7_real(s7_cadr(args));
+    double y = s7_real(s7_caddr(args));
+
+    phys2d_set_gravity(x, y);
+}
+
 #define S7_FUNC(NAME, ARGS) s7_define_function(s7, #NAME, s7_ ##NAME, ARGS, 0, 0, "")
 
 void ffi_load() {
@@ -314,5 +360,7 @@ void ffi_load() {
     S7_FUNC(set_body, 3);
     S7_FUNC(set_body_pos, 4);
     S7_FUNC(phys_cmd, 3);
+    S7_FUNC(phys_q, 2);
+    S7_FUNC(phys_set, 3);
 }
 
diff --git a/source/engine/yugine.c b/source/engine/yugine.c
index 78998f2..6be8b25 100644
--- a/source/engine/yugine.c
+++ b/source/engine/yugine.c
@@ -10,6 +10,10 @@
 #include <stdio.h>
 #include <stdlib.h>
 
+#include "editorstate.h"
+#include "yugine.h"
+#include "2dphysics.h"
+
 
 #ifdef __linux__
 #include <execinfo.h>
@@ -31,6 +35,8 @@ double physMS = 1/120.f;
 double updateMS = 1/60.f;
 
 static int ed = 1;
+static int sim_play = 0;
+static double lastTick;
 
 void seghandle(int sig) {
 #ifdef __linux__
@@ -147,9 +153,7 @@ int main(int argc, char **args) {
     }
 
     openglInit();
-
-    double lastTick;
-
+    sim_stop();
     while (!want_quit()) {
          double elapsed = glfwGetTime() - lastTick;
          deltaT = elapsed;
@@ -158,18 +162,17 @@ int main(int argc, char **args) {
 
          timer_update(lastTick);
 
-         call_updates();
-
-         renderlag += elapsed;
-         physlag += elapsed;
-
-         if (physlag >= physMS) {
-             physlag -= physMS;
-             phys2d_update(physMS);
-             call_physics();
-         }
-
+         if (sim_play) {
+             physlag += elapsed;
+              call_updates();
+              if (physlag >= physMS) {
+                 physlag -= physMS;
+                 phys2d_update(physMS);
+                 call_physics();
+             }
+       }
 
+        renderlag += elapsed;
         if (renderlag >= renderMS) {
             renderlag -= renderMS;
             window_renderall();
@@ -183,3 +186,29 @@ int main(int argc, char **args) {
 
     return 0;
 }
+
+
+
+
+int sim_playing() { return sim_play; }
+void sim_start() {
+    /* Save starting state of everything */
+    sim_play = 1;
+}
+
+void sim_pause() {
+    sim_play = 0;
+}
+
+int sim_paused() {
+    return sim_play;
+}
+
+void sim_stop() {
+    /* Revert starting state of everything from sim_start */
+    sim_play =  0;
+}
+
+void sim_step() {
+
+}
\ No newline at end of file
diff --git a/source/engine/yugine.h b/source/engine/yugine.h
new file mode 100644
index 0000000..cf62ea2
--- /dev/null
+++ b/source/engine/yugine.h
@@ -0,0 +1,12 @@
+#ifndef YUGINE_H
+#define YUGINE_H
+
+int sim_playing();
+int sim_paused();
+void sim_start();
+void sim_pause();
+void sim_stop();
+void sim_step();
+
+
+#endif
\ No newline at end of file
diff --git a/source/scripts/engine.scm b/source/scripts/engine.scm
index 26545f8..52b64ca 100644
--- a/source/scripts/engine.scm
+++ b/source/scripts/engine.scm
@@ -90,8 +90,18 @@
 (define (body_pos! body x y) (set_body_pos body 0 x y))
 (define (body_move! body x y) (set_body_pos body 1 x y))
 
+(define (gravity! x y) (phys_set 0 x y))
+
 (define (b2i val) (if (eq? val #f) 0 1))
 (define (dbg_draw_phys val) (settings_cmd 3 (b2i val)))
+(define (sim_play) (sys_cmd 1))
+(define (sim_stop) (sys_cmd 2))
+(define (sim_pause) (sys_cmd 3))
+(define (sim_step) (sys_cmd 4))
+(define (sim_play?) (sys_cmd 5))
+(define (sim_pause?) (sys_cmd 6))
+
+(define (bodytype? body) (phys_q body 0))
 
 (define-macro (register-phys type body . expr)
     (let ((f (gensym)))
@@ -101,8 +111,8 @@
 	                  ((collide) 0)
 			  ((separate) 3)) ,f))))
 
-(define (collide . expr)
-    (register-phys collide body expr))
+(define-macro (collide . expr)
+    `(register-phys collide body ,@expr))
 
 (define-macro (separate . expr)
     `(register-phys separate body ,@expr))