Over Hill and Under Hill
Minikit #1 (Story Mode)
There are five of these curled skeletons along the path. The first is by the pile of rocks on the upper path, the second is by the stalactite platform on the lower path, the third is on the upper path during the falling boulders, the fourth is on the upper path on the ledge by the mine cart, and the fifth is by the dangling hook on the lower path. Bash them all for a minikit.
Minikit #2 (Free Play)
Just past the cracked rock on the upper path is a small dark cave. Use a wizard character to light the way and grab the minikit inside.
Minikit #3 (Story Mode)
At the beginning of the lower path is a large cracked rock. Buddy up two axe-wielding characters, and bust through to find a minikit inside.
Minikit #4 (Free Play)
When you smash the mine cart forward on the upper path, use a flail character to yank the cart back over, releasing a minikit.
Minikit #5 (Free Play)
At the end of the lower path is Mithril chest. Use Saruman to open it, then build the loose studs it releases into a mining vehicle. Use this to bust up the diamond bricks on the cliff wall and spawn a minikit.
Minikit #6 (Free Play)
A short way up the giant is a Mithril rock. Bust it up with Saruman to reveal the entrance to a secret area. In here, you can dig up a patch of dirt to reveal a cracked block. Use an axe attack on this to win a minikit.
Minikit #7 (Free Play)
In the same area, bust up the debris near the map of Middle-earth to reveal some wraith bricks. Use Frodo's Ring to build a ladder out of these, then climb up to the turnstile. Push this to burn away the map, revealing a minikit.
Minikit #8 (Free Play)
Still in the same area, bust up the two tables for some loose bricks. Build these into two switch pads, then have your two characters stand on either one. This raises up a minikit from below.
Minikit #9 (Story Mode)
As you climb the giant, it will punch its thigh to create a new path. Before crossing up its arm, smash up the rocks in the left corner to reveal a cracked block. Bust through with an axe to receive a minikit.
Minikit #10 (Free Play)
When you end up dazed atop the giant's arm, head out to the tip of its hand. Out here is a Morgul statue; use an evil character like Sauron to bust it up and earn one last minikit.