What are the most challenging hidden mechanics in Little Alchemy 2?

In Little Alchemy 2, some of the most challenging hidden mechanics involve discovering rare or non-intuitive combinations that aren't immediately obvious. These often require creative thinking and experimentation. Here are some tips and steps to uncover these hidden mechanics:

1. Understanding Hidden Elements
- Some elements are "hidden" because they require multiple steps or less obvious combinations. For example:
- Life: Combine Energy and Swamp.
- Human: Combine Life and Clay.
- Time: Combine Sand and Glass (to make Hourglass), then combine Hourglass with Life or Human.

2. Experiment with Abstract Concepts
- Some elements are abstract and require combining concepts rather than physical objects. For example:
- Philosophy: Combine Human and Idea.
- Universe: Combine Time and Space.
- Big: Combine Philosophy and Galaxy.

3. Use the "Everything" Element
- The Everything element is a hidden gem that can be created by combining Universe and Philosophy. This element is a great way to unlock many other hidden combinations.

4. Explore Multi-Step Combinations
- Some elements require multiple steps to create. For example:
- Computer: Combine Electricity and Tool.
- Tool: Combine Metal and Human.
- Electricity: Combine Metal and Energy.

5. Think Outside the Box
- Some combinations are based on wordplay or unconventional logic. For example:
- Baker: Combine Human and Bread.
- Pirate: Combine Human and Sword.
- Zombie: Combine Human and Corpse.

6. Use Hints Sparingly
- If you're stuck, the game offers hints, but use them sparingly to maintain the challenge. Hints can guide you toward the next logical step without giving away the entire solution.

7. Check the Encyclopedia
- The in-game encyclopedia tracks your progress and can help you identify which elements you're missing. It also provides clues about possible combinations.

8. Combine Elements in Different Orders
- Sometimes, the order in which you combine elements matters. For example:
- Water + Fire creates Steam, but Fire + Water might not work the same way.

9. Look for Patterns
- Many elements follow patterns based on real-world logic. For example:
- Combining Earth with Fire creates Lava.
- Combining Lava with Air creates Stone.

10. Experiment with Rare Elements
- Some rare elements, like Time, Life, and Universe, are key to unlocking many hidden combinations. Focus on creating these first to expand your possibilities.

By following these steps and experimenting with different combinations, you'll uncover the most challenging hidden mechanics in Little Alchemy 2. Remember, the game rewards creativity and persistence, so don't be afraid to try unusual combinations!