diff --git a/src/interface/viewport.c b/src/interface/viewport.c
index cbda758778..1238b835ea 100644
--- a/src/interface/viewport.c
+++ b/src/interface/viewport.c
@@ -436,6 +436,27 @@ void sub_6E7DE1(sint16 x, sint16 y, rct_window* w, rct_viewport* viewport){
 	memcpy(viewport, &view_copy, sizeof(rct_viewport));
 }
 
+//rct2: 0x006E7A15
+void viewport_set_underground_flag(int underground, rct_window* window, rct_viewport* viewport)
+{
+	if (window->classification != WC_MAIN_WINDOW)
+	{
+		if (!underground)
+		{
+			int bit = viewport->flags & VIEWPORT_FLAG_UNDERGROUND_INSIDE;
+			viewport->flags &= ~VIEWPORT_FLAG_UNDERGROUND_INSIDE;
+			if (!bit) return;
+		}
+		else
+		{
+			int bit = viewport->flags & VIEWPORT_FLAG_UNDERGROUND_INSIDE;
+			viewport->flags |= VIEWPORT_FLAG_UNDERGROUND_INSIDE;
+			if (bit) return;
+		}
+		window_invalidate(window);
+	}
+}
+
 /**
  * 
  *  rct2: 0x006E7A3A
@@ -455,7 +476,8 @@ void viewport_update_position(rct_window *window)
 		int height = map_element_height(0xFFFF & sprite->unknown.x, 0xFFFF & sprite->unknown.y) & 0xFFFF - 16;
 		int underground = sprite->unknown.z < height;
 
-		RCT2_CALLPROC_X(0x6E7A15, sprite->unknown.x, sprite->unknown.y, sprite->unknown.z, underground, (int)window, (int)viewport, 0);
+		viewport_set_underground_flag(underground, window, viewport);
+		//RCT2_CALLPROC_X(0x6E7A15, sprite->unknown.x, sprite->unknown.y, sprite->unknown.z, underground, (int)window, (int)viewport, 0);
 
 		int center_x, center_y;
 		center_2d_coordinates(sprite->unknown.x, sprite->unknown.y, sprite->unknown.z, &center_x, &center_y, window->viewport);
@@ -473,7 +495,8 @@ void viewport_update_position(rct_window *window)
 	int curr_rotation = RCT2_GLOBAL(RCT2_ADDRESS_CURRENT_ROTATION, uint32);
 	sub_689174(&x, &y, &z, curr_rotation);
 	
-	RCT2_CALLPROC_X(0x006E7A15, x, y, z, 0, (int)window, (int)viewport, 0);
+	viewport_set_underground_flag(0, window, viewport);
+	//RCT2_CALLPROC_X(0x006E7A15, x, y, z, 0, (int)window, (int)viewport, 0);
 
 	//Clamp to the map minimum value
 	int at_map_edge = 0;
diff --git a/src/object.c b/src/object.c
index 7f2ed4eb67..7962d609f0 100644
--- a/src/object.c
+++ b/src/object.c
@@ -385,6 +385,7 @@ int object_calculate_checksum(const rct_object_entry *entry, const char *data, i
 }
 
 /* ebp is made up of 3 pointers: no_elements, unknown, g1_source */
+//rct2: 0x006A9ED1
 int sub_6A9ED1(uint8_t** ebp)
 {
 	int result;
@@ -409,6 +410,7 @@ int sub_6A9ED1(uint8_t** ebp)
 	return result;
 }
 
+//rct2: 0x006DE83E
 int paint_ride_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* dpi, int esi, int ebp)
 {
 	if ((flags & 0xFF) != 3)
@@ -787,6 +789,7 @@ int paint_ride_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* dp
 	}
 }
 
+//rct2: 0x006A8621
 int paint_path_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* dpi, int esi, int ebp)
 {
 	if ((flags & 0xFF) != 3)
@@ -845,6 +848,7 @@ int paint_path_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* dp
 	}
 }
 
+//rct2: 0x00666E42
 int paint_park_entrance_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* dpi, int esi, int ebp)
 {
 	if ((flags & 0xFF) != 3)
@@ -882,11 +886,13 @@ int paint_park_entrance_entry(int flags, int ebx, int ecx, int edx, rct_drawpixe
 			gfx_draw_sprite(dpi, image_id + 1, 24, 68, ebp);
 			gfx_draw_sprite(dpi, image_id, 56, 84, ebp);
 			gfx_draw_sprite(dpi, image_id + 2, 88, 100, ebp);
+			rct2_free(dpi);
 		}
 		return flags;
 	}
 }
 
+//rct2: 0x006E6E2A
 int paint_water_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* dpi, int esi, int ebp)
 {
 	if ((flags & 0xFF) != 3)
@@ -932,7 +938,7 @@ int paint_water_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* d
 	}
 }
 
-//0x0066B355
+//rct2: 0x0066B355
 int paint_stex_entry(int flags, int ebx, int ecx, int edx, rct_drawpixelinfo* dpi, int esi, int ebp)
 {
 	if ((flags & 0xFF) != 3)
diff --git a/src/world/sprite.c b/src/world/sprite.c
index ac4b6a3a07..3c4db8052c 100644
--- a/src/world/sprite.c
+++ b/src/world/sprite.c
@@ -21,6 +21,7 @@
 #include "../addresses.h"
 #include "../interface/viewport.h"
 #include "sprite.h"
+#include "../scenario.h"
 
 rct_sprite* g_sprite_list = RCT2_ADDRESS(RCT2_ADDRESS_SPRITE_LIST, rct_sprite);
 
@@ -30,7 +31,19 @@ rct_sprite* g_sprite_list = RCT2_ADDRESS(RCT2_ADDRESS_SPRITE_LIST, rct_sprite);
  */
 void create_balloon(int x, int y, int z, int colour)
 {
-	RCT2_CALLPROC_X(0x006736C7, x, colour << 8, y, z, 0, 0, 0);
+	rct_sprite* sprite = create_sprite(2);
+	if (sprite != NULL)
+	{
+		sprite->balloon.var_14 = 13;
+		sprite->balloon.var_09 = 22;
+		sprite->balloon.var_15 = 11;
+		sprite->balloon.sprite_identifier = 2;
+		sprite_move(x, y, z, sprite);
+		sprite->balloon.var_01 = 7;
+		sprite->balloon.var_26 = 0;
+		sprite->balloon.colour = colour;
+		sprite->balloon.var_24 = 0;
+	}
 }
 
 /**
@@ -39,7 +52,40 @@ void create_balloon(int x, int y, int z, int colour)
  */
 void create_duck(int targetX, int targetY)
 {
-	RCT2_CALLPROC_X(0x0067440F, targetX, 0, targetY, 0, 0, 0, 0);
+	rct_sprite* sprite = create_sprite(2);
+	if (sprite != NULL)
+	{
+		sprite->duck.sprite_identifier = 2;
+		sprite->duck.var_01 = 8;
+		sprite->duck.var_14 = 9;
+		sprite->duck.var_09 = 0xC;
+		sprite->duck.var_15 = 9;
+		int offset_xy = scenario_rand() & 0x1E;
+		targetX += offset_xy;
+		targetY += offset_xy;
+		sprite->duck.target_x = targetX;
+		sprite->duck.target_y = targetY;
+		uint8 direction = scenario_rand() & 3;
+		switch (direction)
+		{
+		case 0:
+			targetX = 8191 - (scenario_rand() & 0x3F);
+			break;
+		case 1:
+			targetY = scenario_rand() & 0x3F;
+			break;
+		case 2:
+			targetX = scenario_rand() & 0x3F;
+			break;
+		case 3:
+			targetY = 8191 - (scenario_rand() & 0x3F);
+			break;
+		}
+		sprite->duck.sprite_direction = direction << 3;
+		sprite_move(targetX, targetY, 496, sprite);
+		sprite->duck.var_48 = 0;
+		sprite->duck.var_26 = 0;
+	}
 }
 
 /* rct2: 0x006EC473 */
diff --git a/src/world/sprite.h b/src/world/sprite.h
index a9d24991eb..ea1ec8a105 100644
--- a/src/world/sprite.h
+++ b/src/world/sprite.h
@@ -81,6 +81,47 @@ typedef struct {
 	uint32 var_24;
 } rct_litter;
 
+typedef struct {
+	uint8 sprite_identifier;        // 0x00
+	uint8 var_01;					// 0x01
+	uint16 var_02;					// 0x02
+	uint16 next;					// 0x04
+	uint16 previous;				// 0x06
+	uint8 linked_list_type_offset;	// 0x08 Valid values are SPRITE_LINKEDLIST_OFFSET_...
+	uint8 var_09;					// 0x09
+	uint8 pad_0A[0xA];
+	uint8 var_14;					// 0x14
+	uint8 var_15;					// 0x15
+	uint8 pad_16[0xE];
+	uint8 var_24;					// 0x24
+	uint8 pad_25;
+	uint16 var_26;					// 0x26
+	uint8 pad_28[4];
+	uint8 colour;					// 0x2C
+} rct_balloon;
+
+typedef struct {
+	uint8 sprite_identifier;        // 0x00
+	uint8 var_01;					// 0x01
+	uint16 var_02;					// 0x02
+	uint16 next;					// 0x04
+	uint16 previous;				// 0x06
+	uint8 linked_list_type_offset;	// 0x08 Valid values are SPRITE_LINKEDLIST_OFFSET_...
+	uint8 var_09;					// 0x09
+	uint8 pad_0A[0xA];
+	uint8 var_14;					// 0x14
+	uint8 var_15;					// 0x15
+	uint8 pad_16[0x8];
+	uint8 sprite_direction;			// 0x1E
+	uint8 pad_1F[0x7];
+	uint16 var_26;
+	uint8 pad_28[0x8];
+	sint16 target_x;				// 0x30
+	sint16 target_y;				// 0x32
+	uint8 pad_34[0x14];
+	uint8 var_48;					// 0x48
+} rct_duck;
+
 /**
  * Sprite structure.
  * size: 0x0100
@@ -91,6 +132,8 @@ typedef union {
 	rct_peep peep;
 	rct_litter litter;
 	rct_vehicle vehicle;
+	rct_balloon balloon;
+	rct_duck duck;
 } rct_sprite;
 
 // rct2: 0x010E63BC