Soldner-X 2: Final Prototype

There are 17 total challenges you can earn. Here is the complete list:

1. Survivor - Complete the first three stages at any difficulty level without losing any ships.
2. Evasion Master - Play the second stage at any difficulty level without defeating any enemy except the boss and without losing any health. (Three collisions are allowed!)
*3. The Invincible - Clear all seven stages at any difficulty level without losing any ships.
4. Action Fan - Clear all seven stages at any difficulty level on fixed play rank 'B'.
5. Action Master - Clear all seven stages at normal or higher difficulty level on fixed play rank 'S'.
6. Chain Expert - Play the fourth stage at any difficulty level and release at least 16 chain extras.
7. Collector - Collect at least 999 chain rings while playing the second stage at any difficulty level. You may use 'continues'.
*8. Assassin - Clear the fourth stage at normal difficulty level or higher within a time limit of 7:45min. You may use 'continues'.
9. Profiler - Clear the fourth stage at any difficulty level without missing any enemies. (3 errors are allowed)
10. Key Guide - Collect at least 24 keys during a single play-through at any difficulty level.
*11. Little Gunner - Power up any weapon to MAX on any difficulty level before reaching the sixth stage.
*12. Power Gunner - Power up at least two weapons to MAX on any difficulty level before reaching the seventh stage.
13. Rating Expert - Play the second stage at any difficulty level and receive a 'B' rating or higher on the victory screen.
*14. Rating Master - Play the sixth stage at any difficulty level and receive an 'S' rating or higher on the victory screen.
15. Cooperative Expert - Clear all seven stages in 2-player mode at any difficulty level.
*16. Bow Knowledge - Clear all seven stages at normal difficulty level or higher using only the bow weapon.
17. Ultimate Space Rogue - Clear all seven stages at an ultimate fixed nightmare difficulty level. You may use all 'continues' you have available!

Six of these challenges (Survivor, Collector, Action Fan, Chain Expert, Profiler, Rating Expert) are required for aforementioned trophies, starred with an *asterisk are the six others that are recommended for simplicity. If you have a second player who is open to these kind of games, substitute the easy Cooperative Expert for the more difficult Bow Knowledge. Most of these challenges will unlock through the leveling system (viewable under 'Awards' from the main screen), which raises based on your total amount of kills. The final challenge 'Ultimate Space Rogue' unlocks when you hit Level 15. Others will unlock after completing other challenges or collecting a prerequisite amount of keys. You should achieve most of them during normal play. This is the levels list:

Level 1 - Novice
Level 2 - Rookie (2000 kills)
Level 3 - Casual Pilot (2250 kills)
Level 4 - Amateur (2531 kills)
Level 5 - Junior Pilot (2847 kills)
Level 6 - Freelancer (3203 kills)
Level 7 - Regular Pilot (3603 kills)
Level 8 - Advanced Pilot (4054 kills)
Level 9 - Pro Pilot (4561 kills)
Level 10 - Senior Pilot (5131 kills)
Level 11 - Experienced Pilot (5772 kills)
Level 12 - Very Experienced Pilot (6494 kills)
Level 13 - Widely Known Hero (7305 kills)
Level 14 - Galaxy Idol (8218 kills)
Level 15 - Galaxy Superstar (9246 kills)

The number of kills is the number required to reach the next level, not cumulative. You'll need 67,215 kills to reach Level 15. The time needed strictly depends on your play rank, because that dictates the amount of enemies that appear. A stage in which you spend most of your time at play rank 'D' may have only 300 enemies, while the same stage at level 'B' may have closer to 450. Some stages have over 1000 enemies. It strictly depends on your playing style.