User blog comment:CARDADVANTAGE/Jackknife Deck Help?/@comment-4844839-20140713080413

If you are looking to play competitively, I suggest removing all assorted size 3 monsters you have there. As far as I know the only size 3 Armordragon worth running are Death Sickle Dragon and Inferno Armor Dragon.

And since you have Thunderstorm I believe you don't need to play Day of the Dragon. Since you will be leaving your center open most of the time, I'd recommend maxing out Blade Wing Dragon, throw out all Bronze Shield Dragon, and put in some Dragobond instead.

Run 4x Dragoknuckle if you have the budget for it; it's worth it. Jackknife is very gauge hungry.

Also if you're looking for optional decent size 2, Thunder Knights Halberd Dragon is the only one that comes to mind.