diff --git a/CHANGES b/CHANGES
index 08180740d..d6fb54028 100644
--- a/CHANGES
+++ b/CHANGES
@@ -57,6 +57,7 @@ Bugfixes:
  - GBA DMA: Fix temporal sorting of DMAs of different priorities
  - FFmpeg: Fix encoding audio/video queue issues
  - GB Serialize: Fix IRQ pending/EI pending confusion
+ - GB MBC: Improve multicart detection heuristic (fixes mgba.io/i/1177)
 Misc:
  - GBA Timer: Use global cycles for timers
  - GBA: Extend oddly-sized ROMs to full address space (fixes mgba.io/i/722)
diff --git a/src/gb/mbc.c b/src/gb/mbc.c
index 2da6a264e..817b3dc9d 100644
--- a/src/gb/mbc.c
+++ b/src/gb/mbc.c
@@ -95,17 +95,27 @@ void GBMBCSwitchHalfBank(struct GB* gb, int half, int bank) {
 }
 
 static bool _isMulticart(const uint8_t* mem) {
-	bool success = true;
+	bool success;
 	struct VFile* vf;
 
 	vf = VFileFromConstMemory(&mem[GB_SIZE_CART_BANK0 * 0x10], 1024);
-	success = success && GBIsROM(vf);
+	success = GBIsROM(vf);
 	vf->close(vf);
 
+	if (!success) {
+		return false;
+	}
+
 	vf = VFileFromConstMemory(&mem[GB_SIZE_CART_BANK0 * 0x20], 1024);
-	success = success && GBIsROM(vf);
+	success = GBIsROM(vf);
 	vf->close(vf);
 
+	if (!success) {
+		vf = VFileFromConstMemory(&mem[GB_SIZE_CART_BANK0 * 0x30], 1024);
+		success = GBIsROM(vf);
+		vf->close(vf);
+	}
+	
 	return success;
 }