In Hexxit, the End is generated exactly as in Vanilla with the exception of several added Enderman-shaped obsidian towers and the occasional Battle Tower.
The Enderman Towers
In the End, several obsidian towers are shaped as Enderman. In each tower there are two Ender Crystals which will, of course, heal the Ender Dragon. They can be shot with a bow and arrow through the eye holes.
Inside the statues there are ladders which lead to the head and tripwire traps which will cause TNT, which is hidden behind gold blocks, to explode. Inside the head are Sponges which are holding back the lava above them.
There is no loot in the towers apart from 10 gold blocks, quartz blocks and TNT, however the statues are partly underground and at the bottom (under each leg) there are 8 diamond ores. This can be an excellent direction for improving Tinker's Construct weapons as this can be an extremely good source of quartz. The quartz blocks are designed to look like the internal skeleton of the Enderman towers.