diff --git a/Ballance/BMapInspector/Rule.cpp b/Ballance/BMapInspector/Rule.cpp
index f01990e..bd1ce54 100644
--- a/Ballance/BMapInspector/Rule.cpp
+++ b/Ballance/BMapInspector/Rule.cpp
@@ -29,7 +29,10 @@ namespace BMapInspector::Rule {
 		rules.emplace_back(new YYCRule1());
 		rules.emplace_back(new YYCRule2());
 		rules.emplace_back(new YYCRule3());
+		rules.emplace_back(new YYCRule4());		
 		rules.emplace_back(new BBugRule1());
+		rules.emplace_back(new BBugRule2());
+		rules.emplace_back(new BBugRule3());
 		rules.emplace_back(new ZZQRule1());
 		rules.emplace_back(new ZZQRule2());
 		rules.emplace_back(new ZZQRule3());
diff --git a/Ballance/BMapInspector/Rule/BBugRules.cpp b/Ballance/BMapInspector/Rule/BBugRules.cpp
index d0100d9..6106fdb 100644
--- a/Ballance/BMapInspector/Rule/BBugRules.cpp
+++ b/Ballance/BMapInspector/Rule/BBugRules.cpp
@@ -27,4 +27,45 @@ namespace BMapInspector::Rule {
 
 #pragma endregion
 
+#pragma region BBug Rule 2
+
+	constexpr char8_t BBUG2[] = u8"BBUG2";
+
+	BBugRule2::BBugRule2() : IRule() {}
+
+	BBugRule2::~BBugRule2() {}
+
+	std::u8string_view BBugRule2::GetRuleName() const {
+		return BBUG2;
+	}
+
+	void BBugRule2::Check(Reporter::Reporter& reporter, Map::Level& level) const {
+		if (!level.GetTargetCameras().empty()) {
+			reporter.WriteInfo(BBUG2, u8"Using camera in map is not suggested.");
+		}
+	}
+
+#pragma endregion
+
+#pragma region BBug Rule 3
+
+	constexpr char8_t BBUG3[] = u8"BBUG3";
+
+	BBugRule3::BBugRule3() : IRule() {}
+
+	BBugRule3::~BBugRule3() {}
+
+	std::u8string_view BBugRule3::GetRuleName() const {
+		return BBUG3;
+	}
+
+	void BBugRule3::Check(Reporter::Reporter& reporter, Map::Level& level) const {
+		// TODO:
+		// This function is already presented in Ballance Blender Plugin,
+		// so I don't want write it in there now.
+		// Write this if I have spare time in future.
+	}
+
+#pragma endregion
+
 } // namespace BMapInspector::Rule
diff --git a/Ballance/BMapInspector/Rule/BBugRules.hpp b/Ballance/BMapInspector/Rule/BBugRules.hpp
index 428298d..8f13d32 100644
--- a/Ballance/BMapInspector/Rule/BBugRules.hpp
+++ b/Ballance/BMapInspector/Rule/BBugRules.hpp
@@ -19,4 +19,36 @@ namespace BMapInspector::Rule {
 		void Check(Reporter::Reporter& reporter, Map::Level& level) const override;
 	};
 
+	/**
+	 * @brief BBug Rule 2
+	 * @details
+	 * Using camera in map is not suggested.
+	 */
+	class BBugRule2 : public IRule {
+	public:
+		BBugRule2();
+		virtual ~BBugRule2();
+		YYCC_DELETE_COPY_MOVE(BBugRule2)
+
+	public:
+		std::u8string_view GetRuleName() const override;
+		void Check(Reporter::Reporter& reporter, Map::Level& level) const override;
+	};
+
+	/**
+	 * @brief BBug Rule 3
+	 * @details
+	 * Check whether the parameters of all materials is same with Ballance vanilla settings.
+	 */
+	class BBugRule3 : public IRule {
+	public:
+		BBugRule3();
+		virtual ~BBugRule3();
+		YYCC_DELETE_COPY_MOVE(BBugRule3)
+
+	public:
+		std::u8string_view GetRuleName() const override;
+		void Check(Reporter::Reporter& reporter, Map::Level& level) const override;
+	};
+
 }
diff --git a/Ballance/BMapInspector/Rule/Shared.hpp b/Ballance/BMapInspector/Rule/Shared.hpp
index 2b69f15..94d0d08 100644
--- a/Ballance/BMapInspector/Rule/Shared.hpp
+++ b/Ballance/BMapInspector/Rule/Shared.hpp
@@ -62,8 +62,178 @@ namespace BMapInspector::Rule::Shared {
 		// clang-format off
 		constexpr char8_t RAIL_ENVIRONMENT[] = u8"Rail_Environment.bmp";
 		constexpr char8_t LATERNE_VERLAUF[] = u8"Laterne_Verlauf.tga";
-		// clang-format on
 
+
+		constexpr std::array OPAQUE_TEXS{
+			u8"atari.bmp",
+			u8"Ball_LightningSphere1.bmp",
+			u8"Ball_LightningSphere2.bmp",
+			u8"Ball_LightningSphere3.bmp",
+			u8"Ball_Paper.bmp",
+			u8"Ball_Stone.bmp",
+			u8"Ball_Wood.bmp",
+			u8"Brick.bmp",
+			u8"Column_beige.bmp",
+			u8"Column_blue.bmp",
+			u8"Dome.bmp",
+			u8"DomeEnvironment.bmp",
+			u8"ExtraBall.bmp",
+			u8"ExtraParticle.bmp",
+			u8"E_Holzbeschlag.bmp",
+			u8"FloorGlow.bmp",
+			u8"Floor_Side.bmp",
+			u8"Floor_Top_Border.bmp",
+			u8"Floor_Top_Borderless.bmp",
+			u8"Floor_Top_Checkpoint.bmp",
+			u8"Floor_Top_Flat.bmp",
+			u8"Floor_Top_Profil.bmp",
+			u8"Floor_Top_ProfilFlat.bmp",
+			u8"Gravitylogo_intro.bmp",
+			u8"HardShadow.bmp",
+			u8"Laterne_Glas.bmp",
+			u8"Logo.bmp",
+			u8"Metal_stained.bmp",
+			u8"Misc_Ufo.bmp",
+			u8"Misc_UFO_Flash.bmp",
+			u8"Modul03_Floor.bmp",
+			u8"Modul03_Wall.bmp",
+			u8"Modul11_13_Wood.bmp",
+			u8"Modul11_Wood.bmp",
+			u8"Modul15.bmp",
+			u8"Modul16.bmp",
+			u8"Modul18.bmp",
+			u8"Modul30_d_Seiten.bmp",
+			u8"Particle_Flames.bmp",
+			u8"Particle_Smoke.bmp",
+			u8"PE_Bal_balloons.bmp",
+			u8"PE_Bal_platform.bmp",
+			u8"PE_Ufo_env.bmp",
+			u8"P_Extra_Life_Oil.bmp",
+			u8"P_Extra_Life_Particle.bmp",
+			u8"P_Extra_Life_Shadow.bmp",
+			u8"Rail_Environment.bmp",
+			u8"sandsack.bmp",
+			u8"SkyLayer.bmp",
+			u8"Sky_Vortex.bmp",
+			u8"Stick_Stripes.bmp",
+			u8"Target.bmp",
+			u8"Tower_Roof.bmp",
+			u8"Trafo_Environment.bmp",
+			u8"Trafo_FlashField.bmp",
+			u8"Wood_Metal.bmp",
+			u8"Wood_MetalStripes.bmp",
+			u8"Wood_Misc.bmp",
+			u8"Wood_Nailed.bmp",
+			u8"Wood_Old.bmp",
+			u8"Wood_Panel.bmp",
+			u8"Wood_Plain.bmp",
+			u8"Wood_Plain2.bmp",
+			u8"Wood_Raft.bmp",
+		};
+		constexpr std::array TRANSPARENT_TEXS{
+			u8"Button01_deselect.tga",
+			u8"Button01_select.tga",
+			u8"Button01_special.tga",
+			u8"Column_beige_fade.tga",
+			u8"Cursor.tga",
+			u8"DomeShadow.tga",
+			u8"Font_1.tga",
+			u8"Laterne_Schatten.tga",
+			u8"Laterne_Verlauf.tga",
+			u8"Modul18_Gitter.tga",
+			u8"Pfeil.tga",
+			u8"Stick_Bottom.tga",
+			u8"Trafo_Shadow_Big.tga",
+			u8"Tut_Pfeil01.tga",
+			u8"Tut_Pfeil_Hoch.tga",
+			u8"Wolken_intro.tga",
+		};
+
+		constexpr std::array ALL{
+			// u8"atari.avi",
+			u8"atari.bmp",
+			u8"Ball_LightningSphere1.bmp",
+			u8"Ball_LightningSphere2.bmp",
+			u8"Ball_LightningSphere3.bmp",
+			u8"Ball_Paper.bmp",
+			u8"Ball_Stone.bmp",
+			u8"Ball_Wood.bmp",
+			u8"Brick.bmp",
+			u8"Button01_deselect.tga",
+			u8"Button01_select.tga",
+			u8"Button01_special.tga",
+			u8"Column_beige.bmp",
+			u8"Column_beige_fade.tga",
+			u8"Column_blue.bmp",
+			u8"Cursor.tga",
+			u8"Dome.bmp",
+			u8"DomeEnvironment.bmp",
+			u8"DomeShadow.tga",
+			u8"ExtraBall.bmp",
+			u8"ExtraParticle.bmp",
+			u8"E_Holzbeschlag.bmp",
+			u8"FloorGlow.bmp",
+			u8"Floor_Side.bmp",
+			u8"Floor_Top_Border.bmp",
+			u8"Floor_Top_Borderless.bmp",
+			u8"Floor_Top_Checkpoint.bmp",
+			u8"Floor_Top_Flat.bmp",
+			u8"Floor_Top_Profil.bmp",
+			u8"Floor_Top_ProfilFlat.bmp",
+			u8"Font_1.tga",
+			u8"Gravitylogo_intro.bmp",
+			u8"HardShadow.bmp",
+			u8"Laterne_Glas.bmp",
+			u8"Laterne_Schatten.tga",
+			u8"Laterne_Verlauf.tga",
+			u8"Logo.bmp",
+			u8"Metal_stained.bmp",
+			u8"Misc_Ufo.bmp",
+			u8"Misc_UFO_Flash.bmp",
+			u8"Modul03_Floor.bmp",
+			u8"Modul03_Wall.bmp",
+			u8"Modul11_13_Wood.bmp",
+			u8"Modul11_Wood.bmp",
+			u8"Modul15.bmp",
+			u8"Modul16.bmp",
+			u8"Modul18.bmp",
+			u8"Modul18_Gitter.tga",
+			u8"Modul30_d_Seiten.bmp",
+			u8"Particle_Flames.bmp",
+			u8"Particle_Smoke.bmp",
+			u8"PE_Bal_balloons.bmp",
+			u8"PE_Bal_platform.bmp",
+			u8"PE_Ufo_env.bmp",
+			u8"Pfeil.tga",
+			u8"P_Extra_Life_Oil.bmp",
+			u8"P_Extra_Life_Particle.bmp",
+			u8"P_Extra_Life_Shadow.bmp",
+			u8"Rail_Environment.bmp",
+			u8"sandsack.bmp",
+			u8"SkyLayer.bmp",
+			u8"Sky_Vortex.bmp",
+			u8"Stick_Bottom.tga",
+			u8"Stick_Stripes.bmp",
+			u8"Target.bmp",
+			u8"Tower_Roof.bmp",
+			u8"Trafo_Environment.bmp",
+			u8"Trafo_FlashField.bmp",
+			u8"Trafo_Shadow_Big.tga",
+			u8"Tut_Pfeil01.tga",
+			u8"Tut_Pfeil_Hoch.tga",
+			u8"Wolken_intro.tga",
+			u8"Wood_Metal.bmp",
+			u8"Wood_MetalStripes.bmp",
+			u8"Wood_Misc.bmp",
+			u8"Wood_Nailed.bmp",
+			u8"Wood_Old.bmp",
+			u8"Wood_Panel.bmp",
+			u8"Wood_Plain.bmp",
+			u8"Wood_Plain2.bmp",
+			u8"Wood_Raft.bmp",
+		};
+
+		// clang-format on
 	} // namespace TextureNames
 
 #pragma endregion
@@ -173,8 +343,8 @@ namespace BMapInspector::Rule::Shared {
 		return yycc::string::op::join(
 		    [&cache, &first, &last]() -> std::optional<std::u8string_view> {
 			    if (first == last) return std::nullopt;
-				// YYC MARK:
-				// We must use "cache", otherwise "use after free" will occur.
+			    // YYC MARK:
+			    // We must use "cache", otherwise "use after free" will occur.
 			    cache = QuoteObjectName(*(first++));
 			    return cache;
 		    },
diff --git a/Ballance/BMapInspector/Rule/YYCRules.cpp b/Ballance/BMapInspector/Rule/YYCRules.cpp
index 88a01c7..a1b0545 100644
--- a/Ballance/BMapInspector/Rule/YYCRules.cpp
+++ b/Ballance/BMapInspector/Rule/YYCRules.cpp
@@ -14,6 +14,7 @@ namespace L = LibCmo;
 namespace C = LibCmo::CK2;
 namespace V = LibCmo::VxMath;
 namespace O = LibCmo::CK2::ObjImpls;
+namespace strop = yycc::string::op;
 
 namespace BMapInspector::Rule {
 
@@ -246,7 +247,7 @@ namespace BMapInspector::Rule {
 			if (filename == nullptr) {
 				combiner.update(nullptr);
 			} else {
-				auto lower_filename = yycc::string::op::to_lower(filename);
+				auto lower_filename = strop::to_lower(filename);
 				combiner.update(lower_filename);
 			}
 			combiner.update(texdata.GetSaveOptions());
@@ -628,4 +629,72 @@ namespace BMapInspector::Rule {
 
 #pragma endregion
 
+#pragma region YYC Rule 4
+
+	constexpr char8_t YYC4[] = u8"YYC4";
+
+	YYCRule4::YYCRule4() : IRule() {}
+
+	YYCRule4::~YYCRule4() {}
+
+	std::u8string_view YYCRule4::GetRuleName() const {
+		return YYC4;
+	}
+
+	void YYCRule4::Check(Reporter::Reporter& reporter, Map::Level& level) const {
+		// Build lowercase texture name set first.
+		std::set<std::u8string> opaque_texs;
+		for (const auto* tex_name : Shared::TextureNames::OPAQUE_TEXS) {
+			opaque_texs.emplace(strop::to_lower(tex_name));
+		}
+		std::set<std::u8string> transparent_texs;
+		for (const auto* tex_name : Shared::TextureNames::TRANSPARENT_TEXS) {
+			transparent_texs.emplace(strop::to_lower(tex_name));
+		}
+
+		// Check texture one by one
+		for (auto& tex : level.GetTextures()) {
+			auto tex_filename = tex->GetUnderlyingData().GetSlotFileName(0);
+			if (tex_filename == nullptr) continue;
+
+			auto lower_tex_filename = strop::to_lower(tex_filename);
+			if (opaque_texs.contains(lower_tex_filename)) {
+				if (tex->GetVideoFormat() != V::VX_PIXELFORMAT::_16_ARGB1555) {
+					reporter.FormatWarning(
+					    YYC4,
+					    u8"Texture %s is Ballance opaque texture. But its video format is not ARGB1555. This is mismatched with vanilla Ballance.",
+					    Shared::QuoteObjectName(tex).c_str());
+				}
+			} else if (transparent_texs.contains(lower_tex_filename)) {
+				if (tex->GetVideoFormat() != V::VX_PIXELFORMAT::_32_ARGB8888) {
+					reporter.FormatWarning(
+					    YYC4,
+					    u8"Texture %s is Ballance transparent texture. But its video format is not ARGB8888. This is mismatched with vanilla Ballance.",
+					    Shared::QuoteObjectName(tex).c_str());
+				}
+			} else {
+				switch (tex->GetVideoFormat()) {
+					case V::VX_PIXELFORMAT::_16_ARGB1555:
+						// Do nothing.
+						break;
+					case V::VX_PIXELFORMAT::_32_ARGB8888:
+						reporter.FormatWarning(
+						    YYC4,
+						    u8"Texture %s is not Ballance texture. Its video format is ARGB8888. "
+						    "This may cause useless performance consumption if there is no transparent inside it. Please check whether this is essential.",
+						    Shared::QuoteObjectName(tex).c_str());
+						break;
+					default:
+						reporter.FormatWarning(
+						    YYC4,
+						    u8"Texture %s is not Ballance texture. Its video format is not ARGB1555 or ARGB8888. "
+						    "This is mismatched with vanilla Ballance. Please set it to ARGB1555 for opaque texture, or ARGB8888 for transaprent texture, "
+							"except special scenario.",
+						    Shared::QuoteObjectName(tex).c_str());
+						break;
+				}
+			}
+		}
+	}
+
 } // namespace BMapInspector::Rule
diff --git a/Ballance/BMapInspector/Rule/YYCRules.hpp b/Ballance/BMapInspector/Rule/YYCRules.hpp
index d043dbe..28da1b6 100644
--- a/Ballance/BMapInspector/Rule/YYCRules.hpp
+++ b/Ballance/BMapInspector/Rule/YYCRules.hpp
@@ -53,4 +53,22 @@ namespace BMapInspector::Rule {
 		void Check(Reporter::Reporter& reporter, Map::Level& level) const override;
 	};
 
+	/**
+	 * @brief YYC12345 Rule 4
+	 * @details
+	 * \li Check the video format for opaque and transparent texture respectively.
+	 * \li Warning for video format which is not used by vanilla Ballance.
+	 * \li Warning for transparent used video format in non-Ballance textures to conserve resources.
+	 */
+	class YYCRule4 : public IRule {
+	public:
+		YYCRule4();
+		virtual ~YYCRule4();
+		YYCC_DELETE_COPY_MOVE(YYCRule4)
+
+	public:
+		std::u8string_view GetRuleName() const override;
+		void Check(Reporter::Reporter& reporter, Map::Level& level) const override;
+	};
+
 }