There are many ways throughout Neopia to train your pet to make it a complete badass in the Battledome. I'm not going to get into what stats you should train, or to what levels. I'm merely here to teach you the methods you can use to train those stats up until you can destroy ANYTHING.
The Academy
--------------------------
The Academy is located on Krawk Island, and they only accept Dubloons as payment for your pets traning. The price is good, but the downside is the insane waiting times for each course to finish. If you're funding a BD pet, you're probably using Abrosia, and can afford to skip The Academy entirely. If not, then stock up on Dubloons, and hold on tight, because towards the end, it'll take a whopping 10 hours for a course to finish, which means you'll only be able to get in two a day! (Depending on if you sleep or not.)
The maximum possible courses per week, from levels 31-40 is 16.8, as long as you instantly put your pet back onto another course, meaning you could do approximately 67 courses per month at this length of time, compared to an amazing 240 per month at the Training School at the same levels.
The Training School
----------------------------
As mentioned above, the Training School is more expensive, but has much shorter times per course at equal levels, not nearing 10 hours until level 100, and taking only 3 hours at levels 21-40, compared to the 10 hours taken at The Academy per course. The Training School is the place to start if you're using Abrosia to fund your training, and if you're using the Auto Trainer, (And you should be) then you're already training here, and may continue to up to, and including, level 250.
From levels 201-250, it's going to take you a full day for your pet to complete it's course, which is going to suck, but there are time saving (Yet money draining) alternatives which I'll talk about later. With the average price of codestones floating between 5K-6K (Not saying these are the prices for all of them, just the averages) it'll probably cost you from 40K-50K per course at these levels, which is nothing compared to the alternative methods.
In this school, you can also train HP with this formula: (Level*3)+3. You should use this to your advantage to get the most out of your training, and save some NP. I believe the Auto Trainer does this anyways. (?)
The Ninja School
------------------------------
At the Ninja School, you can train your pets from level 250+ and guess what! The time it takes to complete a course has gone down drastically! Now it only takes 4 hours per course at levels 250-299, and the times go up by 2 hours every 100 levels. (Maxing out at 12 hours.) In order to take a course here, you need Red Codestones. You can usually find these quite easily in shops and trades, or you can make them by combining the list of codestones you see at Techo Mountain. Combining these gives you a random Red Codestone, which you may or may not need at the time.
I have never gotten to this school myself, but from what I've read, the HP exploit doesn't work in this school, so you'll need to train all your stats evenly for a while.
Kitchen Quests
------------------------------
While doing the Kitchen Quests on Mystery Island, you have approximately a 33% chance to receive a random stat boost, to a random pet. It's best to do these if you only have one pet, and if the cost of the quest is less than or equal to the cost of one course at the training school of your choice.
Faerie Quests
-------------------------------
If you recieve a Faerie Quest while surfing Neo, then make sure you do it! If you're not interested in training Agility, then don't do Air Faerie quests, but I suggest doing them anyways if they're cheap.
Negging
--------------------------------
Negging is the practice of feeding your pets Neggs in order to raise their stats. There are certain Neggs that are used most often with Negg training, but I will list them all here, (sans prices) for you to browse through.
Remember, you can only feed your pet Neggs when it's hungry, so that limits the stats you can boost per day.
You should figure out which stats you want to train, and which Neggs boost those stats most for the least amount of NP.
Free Training
------------------------------
There are various Dailies that can increase your pets stats for free. Coltzan's Shrine can boost your stats up, and you can visit once every 12 hours.
You can gain Levels from Deadly Dice every night from 12AM-1AM NST.
Turmaculus may raise your Neopets Strength by 1 point, but, he may also eat your petpet, so it's best to have a cheap one attached.
Intelligence can be increased while making NP! You can gain Intelligence by playing Cliffhanger and the Faerie Crossword.
Potions/Non-Filling Items
-----------------------------
There are a variety of potions you can use on your pet to raise their stats, and the best part is, they don't fill up your pets like Neggs do, so you can use them as often as you want!
Shrooms
--------------------------------
Right now, I would just like to say that unless you're crazy rich, I'd avoid training with Shrooms. They're stupid expensive becasue they're retired, and they're not really even worth it. That being said, the only reason I'd ever use them is for bragging rights that I've done so. Here they are:
Other Items
----------------------------------
There are a few more items that change various stats, some are Neggs that don't boost battle stats, and some are just... weird.
And there you have it. A guide on all the ways (currently) to train your pet.
Just realized I forgot to add Kitchen Quests.
Edited by Plunk, 25 October 2011 - 09:15 PM.