I just started playing this (I tried when it first came out and lost it -_-) but I remember back then too that I couldn't figure this shit out even after reading the tutorial. I get that if I have a card that attacks another card (No yellow arrow pointing in the same direction) I take it. However, what I don't understand is when a card battle starts, random ass numbers appear. I throw down my card, the opponent throws down a card the battle begins and I have a number of 6 and they have a number of 52 (lol? wtf) and they take my card. Where are those numbers coming from? is it random? because I feel like I have no control over this at all. The cards I have all say OP 00 and one with OP 10, I've tried multiple things and the results are always different so I can't find a pattern.... please help me duders! :D

FFWiki has your back for Tetra Master, you just basically need to know the 4 numbers on the card. The numbers during battle are somewhat random but have a range based on the rank of the card. First is basically Attack Rank-then attack type (p-or m)-then p defense and then m defense.

THERE IS NO HELP WHEN IT COMES TO TETRA MASTER, THAT GAME IS A PUNISHMENT FOR AN EVIL WORLD

Ahh, good memories. I spent more time playing that than the main game.

@thebunnyhunter: Thanks for that link, it was very helpful but it still seems very random as hell -_- I'll just keep poking around with it.