The final level sees you in a blink-and-you-die race up a GIANT DEATH RAYwhile it's collapsing into a lake of lava and pieces of it are falling down around you while some of it is shooting off electrical arcs. When you finally make it to the top, you fight a giant evil robotic owl who taunts you the whole time while you're flying a jetpack armed with rockets and shooting pieces off of him.
Mz. Ruby throws the established pattern out the window by turning her fight into a rhythm minigame.
The Panda King adapts a constantly-evolving "Flame Fu" moveset to keep you down. Also, you re-do the Panda King fight in Sly 3 to help the Panda King into a Heel-Face Turn to save his daughter and recruit him into the Cooper Gang.
Bentley vs. Jean-Bison. Since Bentley is a turtle and Jean-Bison is a, well, bison, Bentley can't hurt Jean directly. Luckily, the fight takes place in a sawmill, so Bentley can lead the lummox into jets of fire, spinning sawblades, and falling logs. The whole fight has a very Looney Tunes vibe to it.
When talking epic boss battles in Sly 2, we must mention the most greasy sweet boss of all:
Murray vs. Rajan: the fight is basically an electric cage death match between a tiger (who has a lightning spear) and a hippo. Not to mention this snippet before the fight:
Rajan: This is it? This is the Cooper gang I've heard so much about and feared these long hours? Murray: "The Murray" will renew your fear! Rajan: Who's "The Murray"? All I see is a fat pathetic weakling! Murray:...I might be big and not as smart as the other guys...but one thing I'm not...is WEAK!
The climax of the game:
Sly takes up the gunner seat of a helicopter piloted by Carmelita to engage Clock-La in an aerial battle, hammering away at the menace with machinegun fire while shooting down missiles. Oh, and electro-rings. And that's just phase ONE.
Phase TWO consists of Sly pursuing Clock-La through the wreckage of Arpeggio's airship as it comes apart in the skies above Paris. There's too much junk flying around for the helicopter to pursue, so what does Sly do? He jumps OUT of the helicopter and paraglides from one chunk of wreckage to the next, until he catches up with Clock-La and grabs hold, then proceeds to slam away with his cane until they go plunging to earth together. Sly's got some serious fuzzy dice, all right...
The fight with General Tsao. The first part takes place in the canopy of a bamboo forest, where thanks to the ambient energy built up from previous battles there, both Sly and Tsao are able to jump miles in one go. That on its own is cool, but the second part has Tsao show us just how much he's passed the Moral Event Horizon. By the end of the cutscene, you REALLY want to take him down.
The final boss battle in the above episode involves Sly grabbing fireworks, using them to launch himself high into the air, so that he can land on a dragon. That's right: You fight. A fucking. DRAGON.
The pirate captain LeFwee sounds completely lame, but It Makes Sense in Context. One of Bentley's trademark What the Hell, Hero? plans has failed, this one involving a mind-controlled giant squid smashing LeFwee's crew while Bentley risks his life to rescue new team member (and Bentley's unrequited love) Penelope from her imprisonment. Well, the plan itself goes just fine, until LeFwee himself threatens to kill Penelope. Sly whisks her away from danger, but Bentley falls out of his wheelchair, leaving him helpless before LeFwee. However, Penelope comes to the rescue with a sword of her own, and stops LeFwee from harming the turtle with a line that's equal parts Funny and Heartwarming: "Nobody touches that turtle... but me." What ensues is a madcap swashbuckling duel across the mast of LeFwee's pirate ship, followed by a touching cutscene where Bentley finally gets his girl. Of course, then you're informed that the above-mentioned Dimitri is going to join the Cooper Gang. The entire sequence is just a whirlwind of extremely awesome events, least of which being the sweet duel.
The final boss stage is also pretty sweet. Unlike all previous stages, you can't just go running around as Sly pick pocketing guards, every mission has its own unique style of game play. For instance, Dimitri gets to dive into the ocean surrounding Dr. M's fortress to receive Sly's cane, having to avoid various robots and machines along the way. Eventually, he must battle a monstrous cyborg fish controlled by Dr. M, armed with nothing but an underwater shock pistol. He doesn't get the cane, but the experience is rewarding enough on its own.
And then Bentley gets in on the action, taking down Penelope in an all-out robot-suit brawl.
The fight with Ms. Decibel allows Sly to once again use his father's developed technique of walking on light beams, which he had to do to follow Ms. Decibel, all while avoiding the lightning spheres running down them.
The final boss with Le Paradox involves Sly sword-fighting Le Paradox while flowing through a time-hole on the destructing blimp.