HAL 21 is an arcade shooter from 1985 that is mechanically similar to Xevious. The player shoots flying enemies and bombs ground targets as the screen scrolls upwards. At specific parts in the stages more powerful boss enemies will appear. Collecting several energy icons will temporarily increase the ship's firepower.
Two player mode, the arcade version's major improvement on the Xevious template, is not available in the PS Mini release.
[source:mobygames]
Distribution : Retail - CommercialPlatform(s) : Playstation 3 (PS3) -
PlayStation Portable (PSP)
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