1.SKAction
2.SKCropNode
3.SKEffectNode
4.SKEmitterNode
5.SKKeyframeSequence
6.SKLabelNode
7.SKNode
8.SKPhysicsBody
9.SKPhysicsContact
10.SKPhysicsJoint
11.SKPhysicsJoint
12.SKScene
13.SKShapeNode
14.SKSpriteNode
15.SKTexture
16.SKTextureAtlas
17.SKTransition
18.SKVideoNode
19.SKView
20.SpriteKit
21.SpriteKitBase
