The most dramatic (and effective) skip in King's Quest II is the death skip to Dracula's island. It is also the trickiest skip in King's Quest II, although still relatively easy.
When Graham drinks from the poisoned lake (with a command like "drink lake" or the shorter "drink sea"), a death animation is triggered but Graham's movement doesn't stop; and since death occurs with some delay, Graham can cross screens before it happens. This saves Graham from actually dying, and leaves him walking across the poisoned lake in a still-continuing death animation, allowing him to reach Dracula's island without the boat.
The death skip isn't specific to a particular spot; the only requirements are that Graham is near the poisoned lake, near the edge of the screen, and drinks from the lake while moving towards that edge. All three routes (Any%, 100% and ScummVM) generally use the skip at the same location, though: at the screen northeast of Dracula's castle and south of the western part of the monastery, moving southwest towards the screen's southern edge. There are several advantages to this location: it can be reached easily; the shape of the shoreline makes executing the skip fairly easy; it is sufficiently far north that Graham is deposited beyond the thorn maze and directly at the castle entrance; and travel distances during the skip are so short that Fast speed can be used without losing time, especially since two productive commands ("wear cross" and "open door") can be typed mid-travel. By using a different location at the western edge of the same screen it is possible to switch to Fastest immediately after entering death animation, and then reach the castle entrance from the west after a lengthy series of zips; but this is actually slower than remaining in Fast and entering the island from the east. Once Graham reaches the island, he snaps back into a normal animation and loses the ability to walk across the poisoned lake.
The death skip can technically be executed at any time, but only becomes useful after reading the third door inscription. If it is used too early Graham will be stuck on Dracula's island; the boat will appear at the shore but doesn't take him back properly, and the skip itself cannot be initiated on the island.
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Two other glitches can also be exploited in King's Quest II speedruns, both in Dracula's castle: the wall clip and the never-ending tumble. The wall clip is used only in the 100% route, to skip the staircase to the tower with the locked trunk. It requires extremely specific circumstances to work, but is nevertheless very easy to execute since it is built directly into a zip-based route. The clip allows Graham, moving northwest, to walk directly through the wall and into the void beyond; there is another wall at the western edge of the void but it doesn't stop Graham, only prevents him from continuing further west. Graham continues to move north, and eventually emerges at the top of the tower.
The never-ending tumble is used only in ScummVM runs, to slightly speed up the walk down the stairs to Dracula's coffin. Roughly midway through the first stairs down, Graham turns north; this sends him tumbling down, but doesn't kill him if the location is right. Instead, he will appear on the next screen further down the stairs, locked in a still-continuing tumbling animation; despite the strange animation, he can continue moving in a mostly normal way and retrieve the key from Dracula's coffin. Exiting the castle eventually restores some semblance of normality. Exploiting this glitch is somewhat dangerous, since the tumble does kill Graham if he's too far up or down.
