cent ▁of ▁B - W ings , ▁where ▁players ▁assume ▁the ▁role ▁of ▁an ▁Al lied ▁League ▁of ▁Cos mic ▁Nations ▁( AL CON ) ▁f ighter ▁pilot ▁taking ▁control ▁of ▁the ▁SW 4 7 5 ▁space ▁f ighter ▁craft ▁in ▁a ▁counter att ack ▁effort ▁to ▁defeat ▁an ▁inv ading ▁al ien ▁race ▁led ▁by ▁Ga ud y ▁on ▁planet ▁Ther on ▁as ▁the ▁main ▁objective . ▁Besides ▁some ▁hel ic op ters ▁taking ▁off , ▁there ▁are ▁no ▁flying ▁enemies ▁in ▁the ▁entire ▁game . ▁As ▁far ▁as ▁vertical ▁scrolling ▁shoot ers ▁go , ▁the ▁title ▁initially ▁appears ▁to ▁be ▁very ▁standard , ▁as ▁players ▁control ▁their ▁craft ▁over ▁a ▁constantly ▁scrolling ▁background ▁and ▁the ▁scen ery ▁never ▁stops ▁moving ▁until ▁a ▁b oss ▁at ▁the ▁end ▁that ▁must ▁be ▁fought ▁before ▁progress ing ▁any ▁further ▁is ▁reached . ▁Play ers ▁have ▁only ▁two ▁weapons ▁at ▁their ▁dispos al : ▁the ▁standard ▁and ▁side ▁sh ots ▁that ▁travel ▁a ▁max ▁distance ▁of ▁half ▁the ▁screen ' s ▁height ▁and ▁length . ▁ ▁The ▁game ' s ▁weapon ▁power - up ▁system ▁takes ▁insp iration ▁from ▁Grad ius ; ▁certain ▁enemies ▁spawn ▁a ▁star - sh aped ▁item ▁upon ▁destruction ▁to ▁be ▁collected , ▁activ ating ▁an ▁upgrade ▁menu ▁at ▁the ▁bottom ▁of ▁the ▁screen ▁that ▁moves ▁a ▁lit ▁cursor ▁through ▁the ▁list ▁of ▁weapon ▁power - ups ▁described ▁below . ▁However , ▁activ ating ▁any ▁weapon ▁power - up ▁increases ▁the ▁ship ' s ▁hit box , ▁making ▁it ▁a ▁bigger