Kaa's riddles quests are interesting, especially for people that like to do some thinking. However some players might get stuck, and even more will simply want to blast through quests to proceed the story.
In this guide, I'll show where to go for each parts of the quest on Bandit players. A guide for Loner players will hopefully follow up some time soon!
The first riddle speaks of a huge radio tower roughly at the center of the map:
First riddle location - tower at the center of the Pit
The tower in the Pit
Be careful when approaching the structure - there are some anomalies around it, and zombie event spawns there very frequently, too. There are a few ways into the tower itself. The door is on the eastern side, but you can also jump in through the hole by first jumping onto the roof of a building to the north-east.
Whichever way you choose, climb up to the top of the concrete part of the tower. From there, you need to use Q button to start climbing up one of the vertical metal bars.
The pole that can be used to climb up
You don't need to climb all the way up - in fact doing so will likely kill you. The clue is in a backpack on 3rd horizontal bar, counting from bottom one. The backpack is on the north-eastern corner.
Sometimes electric anomalies might be in your way. The way I handled it was just sprint through them and then heal up. But be careful!
First riddle backpack
This riddle takes you to a small house on the western end of Agroprom.
Second riddle location - house on the lake in western Agroprom
The house and its surroundings are filled with anomalies, so be careful - I recommend you pick up a scientist armor, and definitely avoid the pink-ish spots on the ground! I personally swim from the eastern side and sprint through whirligig anomaly towards the entrance. Once at the entrance, I heal up, and then sprint through the house to the far end corner, where anomalies don't hurt me. When done this way, you'll see a backpack:
Second riddle backpack
STALKER series veterans will have some nostalgia breeze. The riddle clearly speaks of the place where we began our journey in STALKER Shadow of Chernobyl as The Marked One - Sidorovich's bunker.
Third riddle location - Sidorovich's bunker
Sidorovich is long gone in the world of Stalcraft (or at least I think so?), but the backpack itself is on the bed behind the counter. There isn't anything complex in getting to it, but keep in mind this is Loners' area, so keep your eye on the proximity counter - I did get some PvP in this very bunker when doing this quest during Beta.
Third riddle backpack
To solve the last riddle, first head to Dump/Garbage and go to the lake on the north, just south of the entrance to the Bar. Jump into the water, and you'll see a flare on the bottom of the lake, roughly in the middle (screenshot coming later - sorry, was being chased by enemy players!).
Fourth riddle location - the lake in the northern Dump
When you approach it, a bubble anomaly will teleport you on top of a building in Agroprom. Go inside through a hatch, and you'll find Kaa on the middle floor. Speak to him to end the quest.
Kaa at the final riddle
Fourth riddle teleport location
Once done, jump down to the ground floor. There will be an another bubble anomaly - when you walk into it, it'll teleport you right outside of the building. You can now return to Solyannikov in The Pit.