 The stage structure is different from other games in the series . After the introduction level , the player can only choose between three Robot Masters . Defeating Cold Man unlocks Burner Man and Pirate Man ; defeating Astro Man unlocks Dynamo Man , Tengu Man , and Pirate Man ; and defeating Ground Man unlocks Magic Man and Tengu Man . Clearing one of these unlocked stages opens the way to a security room where the player must destroy a series of crystals with obtained Robot Master weapons . Bypassing all eight crystals opens the way to the fortress stages . In a similar fashion to previous installments in the series , enemies often drop bolts after they are destroyed , and these can be exchanged for various restorative items and upgrades . However , unlike in Mega Man 7 the security cavern offers a way to obtain large amounts of bolts without having to repeatedly visit stages . Some upgrades are unique to either character , such as Mega Man 's ability to call on his dog Rush to search for items , or an adaptor for Bass to combine with his wolf Treble to temporarily fly . Also distributed throughout the introduction and Robot Master levels are a collection of 100 data CDs that contain information on many prominent characters in the series . Most of the CDs are hidden either behind obstacles that need to be destroyed with a special weapon or accessed with a character @-@ specific ability , making it impossible to collect them all on a single playthrough . CDs collected in each playthrough are permanently placed in a database and remain unlocked after beating the game . Saved games are used in place of the series ' traditional password system . 
 The stage structure <a href='drop_aux' title='1'><mark>is</mark></a>different from other games in the series . After the introduction level , the player can only choose between three Robot Masters . Defeating Cold Man <a href='uninflect' title='2'><mark>unlocks</mark></a> Burner Man and Pirate Man ; defeating Astro Man <a href='uninflect' title='3'><mark>unlocks</mark></a> Dynamo Man , Tengu Man , and Pirate Man ; and defeating Ground Man <a href='uninflect' title='4'><mark>unlocks</mark></a> Magic Man and Tengu Man . Clearing one of these unlocked stages <a href='uninflect' title='5'><mark>opens</mark></a> the way to a security room where the player must destroy a series of crystals with obtained Robot Master weapons . Bypassing all eight crystals <a href='uninflect' title='6'><mark>opens</mark></a> the way to the fortress stages . In a similar fashion to previous installments in the series , enemies often drop bolts after they are destroyed , and these can be exchanged for various restorative items and upgrades . However , unlike in Mega Man 7 the security cavern <a href='uninflect' title='7'><mark>offers</mark></a> a way to obtain large amounts of bolts without having to repeatedly visit stages . Some upgrades <a href='drop_aux' title='8'><mark>are</mark></a>unique to either character , such as Mega Man <a href='null_genetive' title='9'><mark>'s</mark></a>ability to call on his dog Rush to search for items , or an adaptor for Bass to combine with his wolf Treble to temporarily fly . Also distributed throughout the introduction and Robot Master levels <a href='drop_aux' title='10'><mark>are</mark></a>a collection of 100 data CDs <a href='null_relcl' title='11'><mark>that</mark></a>contain information on many prominent characters in the series . Most of the CDs are hidden either behind obstacles <a href='null_relcl' title='12'><mark>that</mark></a>need to be destroyed with a special weapon or accessed with a character @-@ specific ability , making it impossible to collect them all on a single playthrough . CDs collected in each playthrough are permanently placed in a database and remain unlocked after beating the game . Saved games are used in place of the series <a href='null_genetive' title='13'><mark>'</mark></a>traditional password system . 
The stage structure different from other games in the series . After the introduction level , the player can only choose between three Robot Masters . Defeating Cold Man unlock Burner Man and Pirate Man ; defeating Astro Man unlock Dynamo Man , Tengu Man , and Pirate Man ; and defeating Ground Man unlock Magic Man and Tengu Man . Clearing one of these unlocked stages open the way to a security room where the player must destroy a series of crystals w obtained Robot Master weapons . Bypassing all eight crystals open da way to the fortress stages . In a similar fashion to previous installments in the series , enemies often drop bolts after they are destroyed , and dem can be exchanged fir various restorative items and upgrades . However , unlike in Mega Man 7 the security cavern offer a way to obtain bigass amounts of bolts w/o having to repeatedly visit stages . Some upgrades unique to either character , such as Mega Man  ability to call on his dog Rush to search fir items , or an adaptor fir Bass to combine witwids wolf Treble to temporarily fly . Also distributed throughout the introduction and Robot Master levels a collection of 100 data CDs contain information on many prominent characters in the series . Most of tdaCDs are hidden either behind obstacles gotta b destroyed with a special weapon or accessed with a character @-@ specific ability , making it impossible to collect them all on a single playthrough . CDs collected in each playthrough are permanently placed in a database and remain unlocked after beating thdaame . Saved games r used in place of thedaries  traditional password system .