Welcome to Rivet Wars! It's an awesome game and you can really get into it.
Just got the game, would like to ask two things:
1. The trenches on the map are duckboards that give bonus to move to some units. But, do they give +1 defense and if so is it only from certain angles. If not I'm guessing it's not considered like a trench and for shooting it's wide open regardless of range?
You're correct. They only work as modifiers to movement, not defense. Bunkers give a bonus to defense.
2. Buffs are given to everyone in the grid, so it has to say "Buff" and as an example in fantasy with cavalry that have rapid assault would all get that ? Would the infantry give Runner to the cavalry?
Thanks for your time
The ability has to say buff, otherwise it only affects that particular unit. Many of your "hero" units have buff abilities, it will says so on the bottom right of the card. The infantry Runner ability, as an example, only affects that individual unit.