One more thing i'd like to add (since the above posters are completely correct in all they sai, and gave good information) is that although dressage is judged the exact same, in an eventing dressage test, the lower your score the better, rather than the higher the better. If that makes sense? A lotof combined shows that i've been to (dressage and show jumping) use eventing dressage tests (when I say eventing dressage tests, I simply mean they score it that way, they're the same exact patterns and everything). Combined shows are good to intoduce you and your horse to eventing if you're new to it. Judging from your post, you are. :] Also, if you could find a hunters pace***, or a schooling XC show, that will be good for introducing XC, especially because it's a more relaxed setting, you can take it slower than you would at a serious show, and it's generally a LOT cheaper than a mini trial***.
***Hunters pace- if you didn't know- is almost like school XC, but you are with a group of people. If your horse and you are new to XC then it might be the boost you need for someone to jump in front of you. Preferrably someone whose horse is a bold jumper, and doesn't run out.
****Mini trails- this is what people in my area (I say my area, because I don't know if everyone does or not. That's also why I'm giving you the definition. It's not because I think you're an idiot lol :]) call thre day events that aren't actually three days. I've not much experience in eventing shows, but it seems to me- from what I can see- that you won't actually be spending three days at the show until much higher levels.
Unless they call them "mini trials" elsewhere as well, are you referring to this series? ;) Welcome to NEOMTS
That's how I got into Eventing a couple years ago, when my horse and I first learned to jump we entered at the Intro level, then went up to Very Green last year (and were Champion of the VG Rider division YAY!) :) This year I'm battling back and forth with myself trying to decide if I'll go up to Starter level or enter the first "real" eventing level and go for Beginner Novice!
Breed isn't really an issue in eventing.
You see a lot of Thoroughbreds, for the most part, but at the lower levels most any type of horse can do well. I generally look for a horse that is sound and built well, regardless of the level I plan to compete with it, then I look for something that is reasonably level headed (basically something that won't totally lose it when I ask it to go over something it's never seen before). Something that is willing and has a good work ethic.
If you're looking to go higher than beginner novice/novice/training then something with a lot of scope in its jump is pretty much necessary, along with the other criteria above. But, like I said, breed is pretty much all over the map. Heck, there are ponies that have competed through the upper levels of the sport successfully. It's very individual to each animal.
Like Teddy O'Connor!! (may he rest in peace!) Loved that Super Pony!!! He was only 14.1 or 14.2 I think (my pony's height)! Amazing...
Welcome to the dark side MAwahahahahahaha!!!!!!!!!
I have been eventing for 4-5 years :) love it love it love it.
As for breed, I got 2 thoroughbreds. One is my ex eventer, he's over it and i'm going to take him to dressage only and stop jumping him, he's been eventing or racing his whole life so he diserves to retire from it.
My new horse was free, he was off the track 2 years ago next month. He's 6 and he's getting out there this year :) he's alot braver then my ex eventer ozzie. I walked him over a tarp with in 10 mins yesterday, never encountered one in his life and within 10 mins he was walk trot and cantering and halting on it :) that's how I know that he's going to be good :)
You also need a good relationship with your eventing horse, if your horse does't trust you then he sure isn't going to jump blind off a broken bridge
Enjoy it, it's the best sport in the world!!! *just a little bias*