As the set gets "spoiled" with each update of what new cards can be found, I thought it would be appropriate for a place where you can post what combos(/synergy?) you can find. I will start.
Uncontrollable Jalopy + Dragon Catheter
It makes for an interesting pair of cards. As long as you can keep your Jalopy's strength the highest, it effectively halves the time it takes to make it an unblockable attacker. Along with getting a SPD buff from itself, it also gets a STR bonus from the other card.
So by the time you got your 5 counters on your Jalopy it will have 8/3/6 and will be unblockable. Along with that, every turn afterward, it's SPD and STR will increase by 2. So on the next turn it will be a 10/3/8, then a 12/3/10... you get the picture.
Happy Combo(/Synergy?) Hunting