Soldner-X: Himmelssturmer

The biggest grind in the game. You have to get around 300,000 kills to reach rank 15. Keep playing. Each game takes just over an hour, and you’ll average about 10,000 kills per completed game.

There's an easier way to get this. Credit to RyujiSakujo for the quicker method and the spreadsheet.

Combo Mania / Galaxy Superstar:

I've gathered some data and calculated using it to streamline the process of getting these 2 trophies (rather than just play the game over 30 times = for 30 hours).

Here's the data:
https://dl.dropboxusercontent.com/u/16952797/temp_stuff/soldnerx_kills_chains_data_RyujiSakujo_2013-04-15.xls

What I've done is I've started the Training and played the first part of World 3, then I exit to the main menu and repeat. The "time section" of the spreadsheet is the time taken between selecting "World 3" in Training and returning to the main menu after the first part of the stage. What I mean by "first part" is the part with the debris that cover the whole screen until the cutscene which starts with the words "Approaching the asteroid belt, our pilot...". At that point you enter the second part of World 3 and face a miniboss, this is when I exit to the main menu, just after the cutscene and before the miniboss appears.

If we take a look at "two points of time" in the data, namely the first two rows, we can see that I went from 55225 enemies killed to 59305 enemies killed in 7 minutes 45 seconds. We can also see that I went from 1213 chains to 1288 chains. This means 4080 kills and 75 chains in 7min45sec.

If you use those figures and calculate (if I've done it right...) you should arrive at the conclusion that it would take 9hrs30min to go from 0 kills to 300k kills (Galaxy Superstar), and 5hrs9min to go from 0 chains to 3k chains (Combo Mania).

This of course means that you have to keep an average score of 4080 kills and 75 chains in those 7min45sec runs. It's a tedious and monotonous way of getting the trophies but it should be 3 times faster than playing the game over and over again!