Here are several rules that came up in last weeks game.
The Scouring, Primary Objective 40k6 pg 129
In addition, at the end of the game, each player receives 1 Victory Point for each enemy fast attack unit that has been completely destroyed.
Context: I was under the impression that destroyed Fast Attack units gave 2 VPs. Shawn said "Really?" with a quizical look. Looked it up and yep. I was wrong.
Warpflame Chaos Daemons Codex 6th ed pg 61
If the test is passed all models in that unit gain the Feel No Pain (6+) special rule for the rest of the game.
Context: I thought that the squad gained FNP when it rolled a 6 on the test. Shawn said if they passed. He was right. Need to pay more attention when reading codexes.
Hit & Run 40k6 pg 38
A unit that contains at least one model with this special rule that is locked in combat can choose to leave close combat at the end of any Assault phase. If the unit wishes to do so, it must take an Initiative test.
Context: Slaanesh Fiends wanted to leave combat with Purifiers. Opponent thought Hit & Run was like Sweeping Advance. That the two units had to roll off Initiative+D6 to see if the unit left combat. Informed him that wasn't the case.