diff --git a/.gitignore b/.gitignore
index fbffad63..87691ac0 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,9 +1,12 @@
 build
 build.ninja
+compile_commands.json
+.cache/**
 __pycache__
 out
 .vs
 .vscode
+.zed
 *.szs
 statusTestCases.json
 .env
diff --git a/source/game/system/GhostFile.cc b/source/game/system/GhostFile.cc
index b2d38a02..4d579c19 100644
--- a/source/game/system/GhostFile.cc
+++ b/source/game/system/GhostFile.cc
@@ -141,20 +141,36 @@ bool RawGhostFile::decompress(const u8 *rkg) {
 }
 
 /// @addr{0x8051C120}
-/// @todo Check for valid controller type?
-/// @todo Check lap times sum to race time?
 bool RawGhostFile::isValid(const u8 *rkg) const {
     if (strncmp(reinterpret_cast<const char *>(rkg), "RKGD", 4) != 0) {
         PANIC("RKG header malformed");
         return false;
     }
+    
+    u8 laps = *(rkg+0x10);
+    
+    if (laps > 5) {
+        return false;
+    }
+    
+    Timer finalTime = Timer(parse<u32>(*reinterpret_cast<const u32*>(rkg+0x4)));
+    Timer lapSum = Timer();
+    for (u8 i = 0; i < laps; i++) {
+        Timer lapTime = Timer(parse<u32>(*reinterpret_cast<const u32*>(rkg + 0x11 + (i*3))));
+        lapSum += lapTime;
+    }
 
+    if (finalTime != lapSum) {
+        return false;
+    }
+    
     u32 ids = parse<u32>(*reinterpret_cast<const u32 *>(rkg + 0x8));
     Vehicle vehicle = static_cast<Vehicle>(ids >> 0x1a);
     Character character = static_cast<Character>((ids >> 0x14) & 0x3f);
     u8 year = (ids >> 0xd) & 0x7f;
-    u8 day = (ids >> 0x4) & 0x1f;
     u8 month = (ids >> 0x9) & 0xf;
+    u8 day = (ids >> 0x4) & 0x1f;
+    u8 controllerType = ids & 0xf;
 
     if (vehicle >= Vehicle::Max || character >= Character::Max) {
         return false;
@@ -163,6 +179,10 @@ bool RawGhostFile::isValid(const u8 *rkg) const {
     if (year >= 100 || day >= 32 || month > 12) {
         return false;
     }
+    
+    if (controllerType > 3) {
+        return false;
+    }
 
     // Validate weight class match
     WeightClass charWeight = CharacterToWeight(character);
diff --git a/source/game/system/TimerManager.hh b/source/game/system/TimerManager.hh
index 154351b3..f2b9fc84 100644
--- a/source/game/system/TimerManager.hh
+++ b/source/game/system/TimerManager.hh
@@ -6,7 +6,7 @@ namespace System {
 
 /// @brief A simple struct to represent a lap or race finish time.
 struct Timer {
-    Timer(); ///< @unused Creates a zero'd timer.
+    Timer(); /// Creates a zero'd timer.
     Timer(u16 min_, u8 sec_, u16 mil_);
     Timer(u32 data);
     ~Timer();
@@ -82,7 +82,37 @@ struct Timer {
 
         return Timer(newMin, newSec, newMs);
     }
+    
+    Timer operator+(const Timer &rhs) const {
+        s16 addMin = 0;
+        s16 addSec = 0;
 
+        s16 newMs = rhs.mil + mil;
+        if (newMs > 999) {
+            addSec = 1;
+            newMs -= 1000;
+        }
+
+        s16 newSec = rhs.sec + sec + addSec;
+        if (newSec > 59) {
+            addMin = 1;
+            newSec -= 60;
+        }
+
+        s16 newMin = rhs.min + min + addMin;
+        if (newMin > 999) {
+            newMin = 999;
+            newSec = 59;
+            newMs = 999;
+        }
+
+        return Timer(newMin, newSec, newMs);
+    }
+    
+    Timer &operator+=(const Timer &rhs) {
+        return *this = *this + rhs;
+    }
+    
     u16 min;
     u8 sec;
     u16 mil; ///< @todo We will likely want to expand this to a float for more precise finish times.