Stage 7 (Goblin-town): The first battle with Great Goblin | Walkthrough LEGO The Hobbit Guide

You need to eliminate then goblins

You will fight the first part of the battle with the boss in a small arena but, you will not have too many problems with that. Unlike in the case of the battle with Azog the Defiler, you do not need to worry about stepping outside of the delimited area, because you will then be pushed back into the arena, without losing any health hearts. First of all, you need to defeat ten smaller goblins. While fighting, remember to collect the hearts dropped by the monsters that you defeat, and to tap, rhythmically, the attack key/button in situations, in which the game focuses on the fighting characters (this, usually, occurs in the case of the armored goblins).

Hold down the key for Gandalf's special attack

After you have eliminated ten "regular" goblins, wait for Gandalf to appear near the arena and switch to him. Hold down the special attack key/button. This will lead to another cutscene and to the battle proper with the Grand Goblin, which you are going to fight in a larger arena.

Start attacking the smaller goblins, but pay attention to the actions of the Grand Goblin. Once you notice that the boss picked up a big crate, switch to Kili and use his bow to hit the target with the arrow (the above screenshot). If performed correctly, this will stun the Grand Goblin.

Note- if you fail to use the bow on time, the boss will throw the crate at the characters (the risk of losing health hearts), which will, unnecessarily, extend the battle.

Buddy-Up will allow you to wound the stunned boss

After you have stunned the boss, it is time for you to Buddy-Up, i.e. to pair two characters and attack the Grand Goblin in cooperation. Also in this case, you cannot wait for too long with the cooperation attack, because the boss may return to full health.

You need to use the flail on the crate's catch

Continue attacking the regular goblins and, just like earlier, wait for the moment, in which the Grand Goblin picks up a crate. This time, switch to Dori and attach the flail to the crate's catch. Press the indicated key/button for several times, which will stun the boss. The following part is the same as previously - Buddy-Up (team action) and wound the Grand Goblin.

Switch to Gandalf and fire the magic missile at the crate

You are now close to winning this battle. Attack the regular goblins until the moment, in which the Grand Goblin picks up another crate. Switch to Gandalf and fire the magic projectile at the blue point, on one of the crate's walls. Again, pair any two characters in Buddy-Up and perform a team action on the stunned boss. Thanks to this, you will achieve victory, although this is not the last time that you encounter the Grand Goblin.