POKEMON DIAMOND AND PEARL CATCH TABLE SUBSTITUTIONS GUIDE

Ok, so you've been playing Diamond and Pearl for a while now, and you're all familiar with things like the PokeRadar and the Swarms. But, how do these things actually affect the Pokemon you're able to catch? You've come to the right place to find out. Read on.

Basic Catch Table

The Basic Catch Table is the standardized form that the game uses to determine what Pokemon you might catch in any given area. The same table is used for every area in the game, which is what makes it "standardized." There are 12 different rows in this table. Each row has a percentage and a Pokemon. These percentages never change, but the Pokemon change based on the Location. Note that all the percentages combined will add up to 100%. Every time you have a Wild Pokemon battle, the Catch Table for the area is examined. The number in the percent column determines the odds of finding the Pokemon in the catch column. A key thing to note is that the table assumes that it is Morning. Here's what it looks like:

Now, any Pokemon can occupy any of those slots there. Let's make up our own location, Route 1337. Its catch table will look like so:

So, what does this mean? Well, in any given Wild Pokemon battle, I have a 20% chance of finding a Jigglypuff. Same with Wigglytuff. Snorlax, Dewgong, and Heracross; 10% chance each. 5% for both Mudkip and Ampharos, 4% for Blissey and Seadra, and 1% for Mew. Notice Chansey on that list? It's in both 10% and 1%, meaning I have an 11% chance of seeing one.

Substitutions as Principle

The basic idea behind Substitutions in the Catch Table is this; all the different methods that change what Pokemon you find will modify the Pokemon in the Catch Table for a given area. The percents never change. Each location has its own table of sorts that gets read from to overwrite in the event of Substitution. For Route 1337, the Substitution Table looks like so:

So what does all this mean? The first column is the list of what sort of substitution is being used. The second is the Pokemon that will be substituted INTO the Basic Catch Table. The final column is which slot of the Basic Catch Table the Substitution will overwrite.

Substitutions in Practice

Let's start off with an easy one. Let's say the only thing special going on is that it's now Daytime instead of Morning in my game. This means that a "Daytime Substitution" is happening. On Route 1337, during the Daytime, Deoxys and Mewtwo overwrite slots 3 and 4, Snorlax and Dewgong. So, during the Daytime, Route 1337's Catch Table would look like this:

So, what does this mean for us? Well, now we can catch Deoxys and Mewtwo on Route 1337; we have a 10% chance of seeing each of them every time we enter a Wild Pokemon battle. However, notice that Snorlax and Dewgong are no longer available.

This is why, when looking at the locations on the Psydex, activating certain modifiers can completely remove a location for a Pokemon. Let's say that Snorlax and Dewgong are also available on Routes 1336 and 1338. The Locations page for these two Pokemon would then show them available on Routes 1336, 1337, and 1338; that makes 3 rows per version. However, if you activate the "Daytime" modifier, even though you're looking at Snorlax or Dewgong's Locations page, since they don't become more available during the Daytime, but in fact completely drop off of Route 1337's Catch Table, you'll see an entire row disappear from each version, and only the rows for Route 1336 and Route 1338 will remain.

But what happens when multiple Substitutions are in play at once? You'll notice that each kind of Substitution affects different slots. This means that you can have multiple Substitutions going on at the same time without interfering with each other. Let's go all out and say that it's Daytime, there's a Swarm on Route 1337, we're using the PokeRadar, and we've got our Emerald Cartridge inserted in the DS's GBA slot. Route 1337's Catch Table will now look like this:

Look at how much our Route 1337 has changed. With nothing special going on, it was a 20% chance of finding Jigglypuff or Wigglytuff, 11% chance for Chansey, 10% chance for Snorlax, Dewgong, or Heracross, 5% for Mudkip or Ampharos, 4% for Blissey or Seadra, and 1% for Mew.

Now, we've got a 30% chance of seeing Chansey, 25% chance of seeing Jigglypuff, 15% for Heracross, 10% for Deoxys or Mewtwo, 4% for Rayquaza or Wigglytuff, and 1% for Seadra or Mew.

This is how the game will Substitute Pokemon into a Catch Table depending on the different Alternate Capture Methods which are in effect. The PsyDex's Locations page factors all these things into the equation just as it's explained here.

Substitutions and Catch Tables are relatively complicated things to understand. Hopefully, between this guide, your own experience, and playing around on the Locations tab of the PsyDex, you'll be able to get a better idea of just how Diamond and Pearl works to determine what Pokemon you're able to capture.