My main battle pet is currently T10 with stats averaging ~1630.
My armory consists of the following: With other misc weapons including:
I have the following scrolls currently equipped: x2 Also have laying around: x3 x4
General Strategy
Shinwas Temple Shard + Deadwood Scissorbeak + Shriek of Despair Scroll. Block, attack, and freeze.
Blessed Trident of the Banished One + Deadwood Scissorbeak + Shriek of Despair Scroll. Attack and freeze.
Scientists Specs + Acorn Bomb + Sonar Scream Scroll. Bomb and freeze.
Deadwood Scissorbeak + Captured Eternal Flame + Gelaspell. Attack and attempted freeze.
If frozen: Deadwood Scissorbeak + UltimaPlus Tag + Gelaspell. Attack and attempted freeze.
If not frozen: Deadwood Scissorbeak + Rainbow Vortex + Gelaspell. Attack, block, and attempted freeze.
Then Deadwood Scissorbeak + Blessed Trident of the Banished One + Sonar Scream Scroll. Final shot.
So doing a quick ten battles, it looks like my average damage is close to 4k 5k per. So I'm looking at another 900 battles to reach the top. My question is, does anyone see a better weapon set up or general tactic change that I can use to get more damage per battle? I know that with a T10 this should be possible. I just want to improve my strategy.
[edit] 
My general strategy:
Okay, edited my set a bit by changing out the Helmet for , and removing the Phoenix Quill in favor of the attacking . All my items have mod crystals attached. As for scrolls, I very rarely get to even use the defensive ones, so they're a moot point. Looking any better?
I'll need to look up Subetalodge in a bit, but another thing that hits me right away: I think you should use STS during your first turn to set up freezing. RV comes with a chance to freeze so it'd be a waste to use it together with your 100% freezer. I'd recommend that you use it later in the battle for a chance to freeze.
That makes sense! Looks like RV does have a small chance to freeze, while STS does not. I'll switch up their orders and use the STS to freeze during the first round.
[edit]Looks like I've upped my average damage from 4k to 5k! Sweet.
Okay, I look at my set for my T9 pet who will battle later in the week. Here are a few cheap things I find for her that you might find helpful too: Deadwood Scissorbeak 43-45 icons, 3 mod slots
At T10 you can also use the Captured Eternal Flame as bomb with curse plus chance to freeze. If you've got any slot left in your set you might throw in the Ultimaplus Tag. It comes with medium chance to freeze and attack plus 25% heal. You can use it on the turn when the hydra is frozen.
Ooh, interesting. I'll give the Deadwood and Captured Flame a shot. Not sure if I have the slot to spare for the Tag, but maybe. You've been a huge help!
You should have enough slots for the Tag if you go with a set like this:
8 slots :D
Yup yup! I just did a few runs with this set and it works pretty well. :D Granted, I did buy another SDS since I first posted, so that is a major lifesaver.
Updated my first post for any people scrolling through.