so I've literally been trying to understand SL for like, the past 30 mins, and I still don't get it. (yes, I've played the tutorial, multiple times) How does the attacking work? Is it the total amount of the Value? What does the top and bottom numbers mean? And is the left side of the number the attack value and the right side is the defense value? 

I honestly somehow got to level 10 through luck and trial & error. Can someone help me so that I can finally know what I'm doing wrong

tap the ? At top left part for the tutorial.

If that didin't help its basically a numbers game. the larger the value it will flip the lower value side. ? Coins are randomizers it could lower the value of ur cards up  to -2 and  could increase  it up to +2 to all sides of ur cards placed in the randomizer (use with care). As much as possible i would avoid using them unless i have a really powerful card that it wont matter if its -2. Tip is disable autosave. Play with a villager if you lost, restart. Selim and Ghart card are pretty strong early game.

It is a turn-based game so the numbers are both attack and defense. Four numbers are the direction to fight against the opponent. If you've got the larger number at the top, you should set it below to a card with a lower number at the bottom. The same number goes randomized winning chance plus an extra point is taking from the onboard coin.