Engine
Classes 

AIController
AIScript
AccessControl
Actor
Admin
AmbientSound
Ammo
Ammunition
AnimEditProps
Armor
ArmorPickup
AudioTrigger
AutoLadder
BaseGUIController
BeamEmitter
Bitmap
BitmapMaterial
BlockingVolume
BroadcastHandler
Brush
Camera
Canvas
CheatManager
ClipMarker
ColorModifier
Combiner
Console
ConstantColor
ConstantMaterial
Controller
Crushed
Cubemap
DamageType
Decal
Decoration
DefaultPhysicsVolume
DemoRecSpectator
Door
Effects
Emitter
Engine
FadeColor
Fell
FinalBlend
ForceFeedbackController
Fragment
GameEngine
GameInfo
GameMessage
GameReplicationInfo
GameRules
Gibbed
HUD
ImpactEmitter
Info
Interaction
InteractionMaster
Interactions
InternetInfo
InterpolationPoint
Inventory
InventoryAttachment
InventorySpot
Keypoint
Ladder
LadderVolume
LevelInfo
LevelSummary
LiftCenter
LiftExit
Light
LineOfSightTrigger
LocalMessage
MPClassList
MapList
MatchMakingManager
Material
MeshEditProps
MeshEmitter
MeshSkinList
MessagingSpectator
Modifier
Mover
Mutator
NavigationPoint
Note
Palette
ParticleEmitter
ParticleMaterial
PathNode
Pawn
PhysicsVolume
Pickup
Player
PlayerController
PlayerInput
PlayerReplicationInfo
PlayerStart
PlayerStats
PolyMarker
PotentialClimbWatcher
Powerups
Projectile
Projector
ReachSpec
RenderTargetMaterial
RenderedMaterial
ReplicationInfo
SMActorRotating
SavedMove
ScoreBoard
Scout
SequEditProps
Shader
ShadowBitmapMaterial
ShadowProjector
SinusModifier
SkyZoneInfo
SparkEmitter
SpriteEmitter
StatLog
StatLogFile
StaticMeshActor
Suicided
TeamInfo
Teleporter
TerrainInfo
TestInfo
TestObj
TexEnvMap
TexMatrix
TexModifier
TexOscillator
TexPanner
TexRotator
TexScaler
Texture
Trail
Trigger
TriggerParticleEmitter
Triggers
UseTrigger
Vehicle
VehiclePart
VideoPlayer
VoicePack
Volume
VolumeTimer
WarpZoneInfo
WarpZoneMarker
WayBeacon
Weapon
WeaponAttachment
WeaponPickup
XboxLiveManager
ZoneInfo
ZoneTrigger