OOC Help
So... I'm going to regurgitate some stuff that Neo has told me since I don't have too much to help with yet. I'll try and break a few things down once you've actually attacked, etc. Anyways. If something doesn't make sense don't be afraid to ask and I'll try to explain or I'll get the answer from someone else. -only had one other spar before like a baws and it was also OOC-

Writing Style
Stick to one style of writing (incase you, for some reason, feel like experimenting with POVs) and make sure to check each post before you submit it. Check for details and spelling errors. Ensure that you responded to everything the post gave you to work with. Also, make sure it's coherent and flows. That flowing portion may be difficult to work in. But... remember. This is creative writing, so the attacks shouldn't sound like a list...
Like. "She did this. And then she did this. She felt a blow to her shoulder. So she did this." While that is the good base of it all, you need some emotion flooding through there. Just a heads up for when you start responding.

General Attack/Defense Things
The easiest thing to do, so you don't fall into some kind of power play would be to defend from the attack I just gave you and attack. And then fall into this attack/defend rhythm. I cannot say "she charged directly into the mare, knocking her to the ground before bolting off a few strides," because I don't know if I actually knocked you over. Perhaps your mare jumped off to the side and just barely got nicked by Rasta's shoulder and then she kicked out at Rasta knocking her off balance so the running off would be void. Leave things open enough to not make someone forced into a certain position because you continued on. But leave them closed enough that the person has to respond to your attack somehow and can't just go "I saw her start to turn and backed up a few spaces so I wasn't hit" Of course, that can happen realistically maybe once... depending upon exactly what is happening, but be careful of what's going on around you, where you are in relation to the horse, and just what is behind them/around them.

You also need to keep things realistic. If they get injured you have to take that into account the rest of the battle. Emotion/pain felt should be addressed and taken into account for the rest of your posts. If it's easier on you - make a sticky note and keep it beside your computer so you know where they are injured/what it's effecting so you can keep that in mind.

All That Extra Detail
So, keep in mind the breed difference and the height difference. Yours is an Oldenburg who is 2.1hh taller than Rasta. This makes it a little more difficult to maneuver in a tight space, so be careful about where you are starting to push your horse to. Rasta is currently attempting to knock the larger mare off balance as the center of gravity is different and is attacking her legs (much like a wolf going for the hind legs...). She is also trying to push the large mare closer to the trees so that it is more difficult for her to move around in. Rasta is fine with weaving between trees (though of course her blindness will be taken into account) and she is also quite accustomed to feeling the tiny movements and twists of hooves and shifts of weight to get an idea of where they are going to attempt to move. But, in the process of her concentrating completely upon Flora and being in an unknown terrain (unlike her original land where she had lived there for thousands of years and knew it by heart) she is likely to trip over some rocks or a root or something.

Do not forget the terrain! It doesn't matter how well the horse seems to fight if they start off in a partially cluttered space and it ends up turning into a completely open grass lands with no holes or anything to get in their way.