It's annoying, but you can avoid it almost all the time. There are only three NPCs in the game that use the "Random" rule as a fixed rule: Rowena, Aurifort of the Three Clubs, and Landenel. If "Random" is chosen as a regional rule, just don't play NPCs in that area until the next day (regional rules change every day). And while it's annoying that it affects you and not the NPCs, take comfort in the following two truths: 1) because their card pool is so small, you can write down every card they own so you know what they almost definitely have in their hand, and 2) the Triple Triad AI is horrendous. I've seen quite often a situation where the NPC had two cards and there were two open spaces. Three of the four valid plays would win the game for the NPC. They choose the fourth nearly every time.