My RNG nightmare is over! Thundurus Naive 29/31/28/31/30/31 So, I have some tips for anyone going after roamers. RNG at the house on route 7. If you search this thread you'll find many giving this advice. While the roamer can be KO'ed and respawned by fighting the E4, you'll have a VERY hard time RNGing the IVs due to battles progressing the frame. RNG your roamer last. I decided to go after Thundurus before even getting my Zekrom done, which was probably a mistake. The roamer is probably the most difficult RNG venture in B/W, and you'll be TRAPPED in the Route 7 house until you're done. Even if you can hit your seed, its nature is very hard to control, so you'll likely need to hit your seed many times before you happen upon your goal. So don't start it unless you have a lot of time to devote to the task and don't mind that you'll be stuck in the route 7 house during that time. If you value your sanity you'll want to use your Master Ball. This means that, until you can acquire the other Master Ball in the game, you won't have it available to quickly catch other legendaries you're trying to RNG for calibration purposes. If you put off RNGing the roamer for last there might be a new release of RNG Reporter that might have features that could help make things easier. Who knows, good things come to those who wait, right? I'd recommend putting off the roamer as long as possible. Occasionally recalibrate, confirm frame. Generally, your calibration value will apply to anything you try to RNG in B/W. But, in the case of the roamer, you may want to keep closer tabs on how close you're landing to your goal. I found that I needed to adjust from -40 to -36 for more consistency. You may want to track which Nature you get as part of your calibration process. Though you can't control it directly, it being based on the non-C-Gear RNG process, there probably will be a pattern anyway. If there's anything we've learned about the RNG, it's that it's not really random. If you find yourself often getting the same undesired Natures then you might want to choose another seed, or as Mattj suggested, save before leaving the house to advance the frame on the RNG that controls PID/nature/shininess. While doing this you should check to make sure your roamer's IV spread is landing on the right frame, as well. I found that RNG reporter was reporting my roamer spreads 1 frame earlier than their actual position. So, instead of looking for a spread on frame 4, I chose one on frame 3; when I caught my roamer, the desired IV spread was on frame 4, not 3. This wasn't true when I caught Cobalion: RNG Reporter gave me the correct frame. So check for any inconsistencies. This is probably something that varies from DS to DS. Frame 4 is the default frame your roamer will be generated on after leaving the house if you don't advance the frame. If you compromise for a less-than-perfect IV spread you can save yourself a lot of stress by picking a spread that doesn't require you to advance frames. The roamer appears on specific routes. Depending on what day/time your seed is on, the roamer will appear on one or two routes more often. First, find a route by watching the ticker on one of the route checkpoints. Then ride your bike on and off the route until a thunder storm starts. For the first seed I was going for, it appeared very often on route 6. When I changed seeds, it didn't appear there AT ALL. Route 5 turned out to be the new spot. So that does it for my tips. I won't be trying to RNG my wife's Tornadus any time soon thanks to what a pain Thundurus proved to be. >:( Some day, though. Can't have Raijin without Fujin.