best slots if you want to actually understand what's happening

i'm mostly a poker and roulette guy but i've been looking at slots lately just to see what all the hype is about. problem is, half these games feel like they’ve got a secret language and you never really know why you won or lost. i want something where i can see the math play out, not just endless pop-ups or five layers of bonus stuff that distract from what’s actually going on. i’m not against high variance, but i need to understand the triggers and how the thing actually pays.

does anyone have recommendations for slots where you can actually follow the logic without needing to watch a tutorial or trust some influencer’s chart? i’m fine if it’s simple, or even a bit old school, as long as it isn’t all smoke and mirrors. what’s your go-to for that kind of transparency?