This is the fourth installment on the Star Force series.It's name on japan is (流星のロックマンRyusei no Rokkuman:Shinsei).it introduces Ash Kent and Sigma-Xis,who are ProtoMan of Star force.
The game starts with Geo Stelar stopping a riot made by Speed-up Alias,the last survivor of an alien race (the Speedsters),who self-proclaims himself "QuickMan".Meanwhile,Ash is on Xcell labs when he activates the "Sigma Trigger" security mechanism of an alien ship that was there being researshed by the scientists,releasing Sigma-Xis.He (Sigma-Xis) was an rapidly rotting FM-ian.Then,all of a sudden,both Geo AND Ash get hit by radioactive meteors that trigger transformations in them.Geo now has a MegaBuster as a hand,and "Proto" (Sigma-Xis) has his rotting process sped up by 2000000000 years!Bass,a more evolved FM-ian,also appears.they go to armageddon,a sattellite that can give ProtoMan a new body,and Bass...well,Bass just needs to kill,get it?There are Eight Guardians on the sattelite,One of them being MainFrame,Geo's little half-brother,who is Spout-Dive Man.You must defeat him by last.Afterwards,Bass fuses with what is supposed to be an genetically-engineered version of him,Pandemic,turnig him into BassBA (Beast Ashes)and ProtoMan turns into Neo Proto,who kills many people,while it's implied that he never wished becoming a villain.He teams up with bass using his beast FM ability.megaman also has this ability.Bass Mass-clones himself,but MegaMan defeats them all.Bass rapidly devolves into a Hydra-like monster,his true "Zeta-Xis" form.Megaman Defeats him,but Proto arrives as Kaiser Proto,and kills him for failing to defeat MegaMan.You have to defeat him before the sattelite crashes and blows up.
Finis (The End)
The Game ends as Doctor Neutral finds the Evil Artificial Intelligence D.N.A DataChips of Proto and Bass.who knows what will happen next...?
By gaining all meteor shards and ending the game you can enter the "FlashBack" stage.you use MegaMan.EXE and fight BassBGMP (Beast Gospel,And Mega Proto).