diff --git a/src/mame/drivers/tatsumi.cpp b/src/mame/drivers/tatsumi.cpp
index f79db9dd28b..025c9f397b6 100644
--- a/src/mame/drivers/tatsumi.cpp
+++ b/src/mame/drivers/tatsumi.cpp
@@ -1,5 +1,5 @@
 // license:BSD-3-Clause
-// copyright-holders:Bryan McPhail
+// copyright-holders:Bryan McPhail, Angelo Salese
 /***************************************************************************
 
     Apache 3                                            ATF-011
@@ -195,12 +195,6 @@ WRITE16_MEMBER(cyclwarr_state::bigfight_a40000_w)
 	COMBINE_DATA(&m_bigfight_a40000[offset]);
 }
 
-WRITE16_MEMBER(cyclwarr_state::bigfight_a60000_w)
-{
-	COMBINE_DATA(&m_bigfight_a60000[offset]);
-//	popmessage("%04x",m_bigfight_a60000[offset]);
-}
-
 template<int Bank>
 READ16_MEMBER(cyclwarr_state::cyclwarr_videoram_r)
 {
@@ -341,7 +335,7 @@ void cyclwarr_state::common_map(address_map &map)
 
 	map(0x0a2000, 0x0a2007).w(this, FUNC(cyclwarr_state::video_config_w));
 	map(0x0a4000, 0x0a4001).w(this, FUNC(cyclwarr_state::bigfight_a40000_w));
-	map(0x0a6000, 0x0a6001).w(this, FUNC(cyclwarr_state::bigfight_a60000_w));
+	map(0x0a6000, 0x0a6001).w(this, FUNC(cyclwarr_state::mixing_control_w));
 	map(0x0ac000, 0x0ac003).w(this, FUNC(tatsumi_state::hd6445_crt_w)).umask16(0x00ff);
 
 	map(0x0b8000, 0x0b8001).w(this, FUNC(cyclwarr_state::cyclwarr_sound_w)).umask16(0xff00);
diff --git a/src/mame/includes/tatsumi.h b/src/mame/includes/tatsumi.h
index 163d07ebb98..ce8d1cd7cdb 100644
--- a/src/mame/includes/tatsumi.h
+++ b/src/mame/includes/tatsumi.h
@@ -1,5 +1,5 @@
 // license:BSD-3-Clause
-// copyright-holders:Bryan McPhail
+// copyright-holders:Bryan McPhail, Angelo Salese
 
 #include "sound/okim6295.h"
 #include "sound/ym2151.h"
@@ -68,7 +68,7 @@ public:
 	
 protected:
 	uint8_t m_hd6445_reg[64];
-	void apply_shadow_bitmap(bitmap_rgb32 &bitmap, const rectangle &cliprect, bitmap_ind8 &shadow_bitmap);
+	void apply_shadow_bitmap(bitmap_rgb32 &bitmap, const rectangle &cliprect, bitmap_ind8 &shadow_bitmap, uint8_t xor_output);
 private:
 	uint8_t m_hd6445_address;
 };
@@ -197,7 +197,7 @@ public:
 	DECLARE_WRITE16_MEMBER(cyclwarr_sprite_w);
 	DECLARE_WRITE16_MEMBER(video_config_w);
 	DECLARE_WRITE16_MEMBER(bigfight_a40000_w);
-	DECLARE_WRITE16_MEMBER(bigfight_a60000_w);
+	DECLARE_WRITE16_MEMBER(mixing_control_w);
 	DECLARE_WRITE8_MEMBER(cyclwarr_control_w);
 	DECLARE_WRITE8_MEMBER(cyclwarr_sound_w);
 	DECLARE_WRITE16_MEMBER(output_w);
@@ -235,7 +235,7 @@ private:
 	tilemap_t *m_layer[4];
 
 	uint16_t m_video_config[4];
-	uint16_t m_bigfight_a60000[2];
+	uint16_t m_mixing_control;
 	uint16_t m_bigfight_a40000[2];
 	uint16_t m_bigfight_bank;
 	uint16_t m_bigfight_last_bank;
@@ -246,5 +246,6 @@ private:
 	void tile_expand();
 	void draw_bg(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect, tilemap_t *src, const uint16_t* scrollx, const uint16_t* scrolly, const uint16_t layer_page_size, bool is_road, int hi_priority);
 	void draw_bg_layers(screen_device &screen, bitmap_rgb32 &bitmap, const rectangle &cliprect, int hi_priority);
+	void apply_highlight_bitmap(bitmap_rgb32 &bitmap, const rectangle &cliprect, bitmap_ind8 &highlight_bitmap);
 };
 
diff --git a/src/mame/machine/tatsumi.cpp b/src/mame/machine/tatsumi.cpp
index 5e2d582248c..5588dd688ee 100644
--- a/src/mame/machine/tatsumi.cpp
+++ b/src/mame/machine/tatsumi.cpp
@@ -1,5 +1,5 @@
 // license:BSD-3-Clause
-// copyright-holders:Bryan McPhail
+// copyright-holders:Bryan McPhail, Angelo Salese
 #include "emu.h"
 #include "includes/tatsumi.h"
 #include "sound/okim6295.h"
diff --git a/src/mame/video/tatsumi.cpp b/src/mame/video/tatsumi.cpp
index f5cfa2a20a9..52cfde7c30e 100644
--- a/src/mame/video/tatsumi.cpp
+++ b/src/mame/video/tatsumi.cpp
@@ -1,5 +1,5 @@
 // license:BSD-3-Clause
-// copyright-holders:Bryan McPhail
+// copyright-holders:Bryan McPhail, Angelo Salese
 #include "emu.h"
 #include "includes/tatsumi.h"
 #include "screen.h"
@@ -56,15 +56,18 @@ WRITE16_MEMBER(tatsumi_state::tatsumi_sprite_control_w)
 }
 
 // apply shadowing to underlying layers
-// TODO: it might mix up with the lower palette bank instead 
-void tatsumi_state::apply_shadow_bitmap(bitmap_rgb32 &bitmap, const rectangle &cliprect, bitmap_ind8 &shadow_bitmap)
+// TODO: it might mix up with the lower palette bank instead (color bank 0x1400?)
+void tatsumi_state::apply_shadow_bitmap(bitmap_rgb32 &bitmap, const rectangle &cliprect, bitmap_ind8 &shadow_bitmap, uint8_t xor_output)
 {
 	for(int y=cliprect.min_y;y<cliprect.max_y;y++)
 	{
 		for(int x=cliprect.min_x;x<cliprect.max_x;x++)
 		{
 			uint8_t shadow = shadow_bitmap.pix8(y, x);
-			if(shadow)
+			// xor_output is enabled during Chen boss fight (where shadows have more brightness than everything else)
+			// TODO: transition before fighting him should also black out all the background tilemaps too!? 
+			//       (more evidence that we need to mix with color bank 0x1400 instead of doing true RGB mixing).
+			if(shadow ^ xor_output)
 			{
 				rgb_t shadow_pen = bitmap.pix32(y, x);
 				bitmap.pix32(y, x) = rgb_t(shadow_pen.r() >> 1,shadow_pen.g() >> 1, shadow_pen.b() >> 1);
@@ -702,7 +705,7 @@ uint32_t apache3_state::screen_update_apache3(screen_device &screen, bitmap_rgb3
 	screen.priority().fill(0, cliprect);
 	draw_sprites(screen.priority(),cliprect,1,(m_sprite_control_ram[0xe0]&0x1000) ? 0x1000 : 0); // Alpha pass only
 	draw_sky(bitmap, cliprect, 256, m_apache3_rotate_ctrl[1]);
-	apply_shadow_bitmap(bitmap,cliprect,screen.priority());
+	apply_shadow_bitmap(bitmap,cliprect,screen.priority(), 0);
 //  draw_ground(bitmap, cliprect);
 	draw_sprites(bitmap,cliprect,0, (m_sprite_control_ram[0x20]&0x1000) ? 0x1000 : 0);
 	m_tx_layer->draw(screen, bitmap, cliprect, 0,0);
@@ -1038,7 +1041,7 @@ uint32_t roundup5_state::screen_update_roundup5(screen_device &screen, bitmap_rg
 	draw_landscape(bitmap,cliprect,0);
 	draw_landscape(bitmap,cliprect,1);
 	draw_road(bitmap,cliprect);
-	apply_shadow_bitmap(bitmap,cliprect,screen.priority());
+	apply_shadow_bitmap(bitmap,cliprect,screen.priority(), 0);
 	if(m_control_word & 0x80) // enabled on map screen after a play
 	{
 		m_tx_layer->draw(screen, bitmap, cliprect, 0,0);
@@ -1078,7 +1081,16 @@ WRITE16_MEMBER(cyclwarr_state::video_config_w)
 {
 	COMBINE_DATA(&m_video_config[offset]);
 }
- 
+
+// mixing control (seems to be available only for Big Fight and Cycle Warriors)
+// --x- ---- enabled in Big Fight, disabled in Cycle Warriors (unknown purpose)
+// ---- -x-- enable shadow mixing
+// ---- ---x if 1 invert shadows, i.e. shadows are drawn with original pen while non shadows are halved (Chen stage in Big Fight)
+WRITE16_MEMBER(cyclwarr_state::mixing_control_w)
+{
+	COMBINE_DATA(&m_mixing_control);
+}
+
 template<int Bank>
 TILE_GET_INFO_MEMBER(cyclwarr_state::get_tile_info_bigfight)
 {
@@ -1309,7 +1321,7 @@ uint32_t cyclwarr_state::screen_update_cyclwarr(screen_device &screen, bitmap_rg
 	screen.priority().fill(0, cliprect);
 	draw_sprites(screen.priority(),cliprect,1,(m_sprite_control_ram[0xe0]&0x1000) ? 0x1000 : 0); // Alpha pass only
 	draw_bg_layers(screen, bitmap, cliprect, 0);
-	apply_shadow_bitmap(bitmap,cliprect,screen.priority());
+	apply_shadow_bitmap(bitmap,cliprect,screen.priority(), m_mixing_control & 1);
 	draw_sprites(bitmap,cliprect,0,(m_sprite_control_ram[0xe0]&0x1000) ? 0x1000 : 0);
 	draw_bg_layers(screen, bitmap, cliprect, 1);
 	return 0;