Rockman 4 Minus Infinity aka: Rock Man Minus Infinity
Rockman 4 Minus Infinity is a Rockman 4ROM hack by Pure Sabe. It features new level designs, complex new gimmicks and bosses, as well as lot of enemies from the original classic series.This site contains lots of information on the game.
This game provides examples of:
Abnormal Ammo: Spark. Manbow lets Mega Man shoot light bulbs.
Advancing Boss of Doom: At one point in Ring Man's stage, you encounter a Jumbig that makes short hops towards you and has a high amount of hit points.
Puresabe seems to be a big fan of Rockman World 5 and Mega Man X2. The Cossack bosses are based on the X-Hunters and the Charge Shot looks like the Charge Shot from X2. Some of the enemies and gimmicks from Rockman World 5 show up.
He also seems to like Shadow Man a lot, as the latter is fought several times throughout the game.
Sections of Skull Man's level, which has every kind of platform from the Mega Man series.
Wily Stage 2's last half, which is an Homage to the Gradius series' High Speed Zone stages.
Baleful Polymorph: Toad Man's Toad Spell, when used by him, turns you into a defenseless frog from Kaeru no Tame ni Kane wa Naru. When used by you, it turns enemies (and items) into tiny, harmless toads.
Berserk Button: Pharaoh Man gets upset when Mega Man destroys the statues in his stage and later challenges him to a battle when Mega Man destroys the coffin in his room.
Blackout Basement: The first half of Bright Man's level. You can see the level in general, but not enemies and objects under or over you.
Bonus Boss: Wave Man in Dive Man's Stage and Crash Man in Drill Man's stage. Beat them and unlock the Wire and Balloon Adaptors before the Cossack stages.
Bottomless Pit Rescue Service: If you find and rescue Beat in Skull Man's stage and Cossack Castle Stage 1, he does this for you at the cost of some of your HP for the rest of the stage.
Bright Man has two: the first half of the stage is only lit on your X-axis position, while the second half uses red, blue and green disappearing blocks, which damage you should you be in them when they appear. There are also ladders and Spikes of Doom that function in this manner.
Toad Spell turns the debris Dust Man expels out of his Arm Cannon into toads. When he inhales it back in, he gets damaged instead.
Toad Man, in a homage to Mega Man 2, gets killed in one hit if you use Toad Spell on him. Probably because the Toad Spell cures the Toad status in the Final Fantasy games.
Shadow Man in Toad Man, Bright Man, and Pharaoh Man's stages, as well as Cossack Castle Stage 1.
Whopper and The Trio of Ring Rings in Ring Man's stage, which is a homage to Lololo and Lalala from the Kirby game series.
Hogale and Enker in Dive Man's stage.
Quint and Kabatoncue in Drill Man's stage.
King Gajuras in Skull Man's stage.
Mythology Gag: There are a whole lot of enemies from other Mega Man games, for starters.
The lifebars/HUD from the Game Boy Mega Man games (also known as the Rockman World series) show up for the first half of Bright Man's stage.
HCR Boomerang gains the Power-Up Magnet abilities of its Game Boy version.
Drill Man's stage contains Ring Man's hippo Mini-Boss, which has the blocks of its Game Boy counterpart.
Pluto's Mini-Boss also appears, and Drill Man himself copies Uranus' Desperation Attack of crashing the ceiling down on you.
Pharaoh Man and Drill Man's stages also contain falling blocks from the fourth Game Boy game.
AndLiving Statues of Fire Man, Heat Man, and Flame Man show up at the very end of the former.
An enemy from Aqua Man's stage in Mega Man 8 appears in Dive Man's stage here.
The Balloon Adapter is based on the Rush Jet Adapter from Mega Man 3.
When Crash Man and Wave Man's holograms are defeated, the device used to operate them appears. It's the exact same projector Dr. Wily used for his alien form in Mega Man 2's final battle.
Time Stands Still: If you hold up when you use the Spark. Manbow, all the enemies on the screen except a few get frozen for a few seconds.
Turns Red: All of the Cossack Robot Masters do this.
Unexpected Shmup Level: Cossack Stage 1's second half, which has you ride on the Balloon Adaptor until Shadow Man ambushes you. After the Mini-Boss battle, you do some Sky Surfing with Rush.
Use Recycle Inhaler on Eddie and he turns into a Energy Splitter. However, do that and Eddie won't give you any warnings for Cossack Stage 1 and Wily Stage 2 or show up to give you any powerups in the other stages.
A lesser example can be done, in Dive Man's stage; the Up'N'Down enemy wears a scuba diving mask for its appearance there, but if you shoot it off, it will drown and explode.