I have recreated Stone Golem boss with 2 command block,the command is only work in minecraft 1.9   
The boss fight has two phase
Phase 1
Using bow and arrow to shoot the stone golem and at the same time avoid getting crushed by his stone hand (Seem easy enough)
Phase 2
Attack him with melee weapon, try to hit the cobble stone on his chest to expose the core, you can take damage from attacking the cobble stone
-In this phase, he can summon:
Stone minion:fast and small stone minion
Blast core:basically a small size stone creeper that explode when near player
ground spike: chase down player and deal damge to player

-he has two abilities:
Ground smash:He will jump up and falldown ,create a shock wave stunt and deal damge to player 
Ground dig:He will dig in to the ground and chase player if the player is to far away
When the core is exposed, The boss will be angry and more faster 
COMMANDS :

http://www.mediafire.com/download/u6wrc4k655065kb/Stone_Golem_boss_in_two_%28command%29.rar
(You can also play with my creation on my custom world)
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