Congratulations and welcome back to the Soldner-X Defense Force, Galaxy Warrior!
Well, first thing: When you destroy enemies, most of them leave behind Chain Rings. The more you continue to fire, the more a circular Chain Clock located at the bottom-right of the screen continues to drain.
Once the Chain Clock depletes, you will lose some Chain energy - Chain energy can be seen in the bar connected to the Chain Clock.
To stop the Chain Clock from running down, you stop firing and it recovers a little bit.
Once you grab a Chain Ring, the Chain Clock starts over and you gain Chain energy. Once the bar attached to the Chain Clock fills all the way, the extra will be released!
When you hear the "Chain low" voice, try to collect the nearest Chain Rings you see in order to reset the Chain Clock - or destroy the nearest enemies to find more Chain Rings. It's pretty easy, once you get the hang of it!
EDIT: Now, to attain a bigger score, try to Chain as often as possible, as some of your Extras that are released could be score-related. Pick up as many score-related Extras you see laying around or ones that are dropped, too.
Finally, your play rank is the result of your performance. Try not to get hit by anything. A bar slowly fills at the top-right of the screen as long as you're not getting hit, and when it fills all the way, your play rank increases by one grade (in order of worst to best: G, F, D, C, B, A, S).
The higher your play rank, the higher your current score is multiplied. This goes for what difficulty you're playing on as well.
But i agree with you that every self respecting shmup schould have a nightmare level which only 10 or 20% of the players can finish.
It's probably far below 1% of people who even played on nightmare in SX1, so this number was too low for us. If you consider how many people will 1cc SX2 on extra hard it's probably still going to be far less than 10%.
Rainbow Skies is finally available. Download it on the PS Store for PS4, PS Vita and PS3.
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