We increased the default draw distance. The level radius for the player's level used to be 3, now it is 4.
The main technical advance here is the "fertile radius". The fertile radius determines which chunks contain non-block entities. So all chunks (on a level) outside the fertile radius only contain blocks. The fertile radius for the level of the player is still 3.

Added new weapon mode: the Progressive Rocket. These rockets have a very slow velocity and do not explode, but they have a very high damage per second and damage per ammo.

Added a place called the "Stable Singletons Room" next to the player's emergency waypoint. This room has copies of some of the areas of the world, so it is easy to come back to them later. For example, when you enter I1 and eventually reach a Williston City, you can touch an item which unlocks a door in the I1 block in the Stable Singletons Room. That block contains a copy of I1.

Added three large and challenging areas to I2: Fanatic Spires, Creeping Jeni Plants, and Violets. These require stealth and will help bridge the gap between the early game and the late game.

The primary homing weapon is now much better: it launches a big ball, and if it kills a monster, one minigun primary shot is shot towards every nearby monster.

Rats now move slower and are indicated on your HUD.

Your EMP icon now looks yellow when you are close to the boundary of your EMP sphere, and it looks red when you are outside your EMP sphere. Actually, it considers all EMP spheres you have detonated, and it is red if you are outside all of them. Remember that an EMP sphere only affects monsters on the level where it was detonated.

Replaced white box devices in final boss area with arcades.

Added to the Secret Cave of Jerichos.

Made Oak Tree branches more interesting.

Made quicksand grass 11 have X's on it to differentiate it from quicksand grass 1 through 10. Also we now use less quicksand grass 11 as a border for the edges of quicksand grass 1.

Added a windowed mode.

The algorithm to teleport the player from one chunk to another is now faster. We now reuse more of the chunk tree. Specifically, we keep the old chunk tree up until the level where the source chunk path and the target chunk path differ. That is, we are building off of the old chunk tree trunk. We call this "trunk teleporting".

Made the "Chunk Changes Object Tracker" faster by hashing block paths differently. Loading of chunks is now faster when the player is hundreds of levels deep.