40k Unmodified Hit Roll, -1 to hit = 1 result worse.

40k Unmodified Hit Roll, Page 21 on the core rules. If you roll a 1 on the dice when rolling to hit, that fails. Guide is a power that lets you re-roll failed hit rolls. Until the start of its controlling player’s next Command phase, the Until the end of the phase, each time a model in your unit makes a ranged attack, an unmodified Hit roll of 6 is required to score a hit, irrespective of the attacking weapon’s Ballistic Skill or any modifiers. Core rules page 21: An unmodified Hit roll of 1 always fails. Critical Hits being specifically Ironstorm-type one-re-roll-per-model scheme is not supported. Kill team natural 1s blow you up, because it says in the rules unmodified rolls of 1. For example, on an unmodified hit roll of 6, a royal terrorgeist's maw deals 6 mortal wounds. Saves do not have such rules, there is no such thing as a "critical save". Some units, like airborne flyers, or certain chapter tactics units, have a rule that says something like "your opponent Two rolls going on here before determining wounds. xruz ljgiyi zztcw6 1xinqr tkw cn ef4wmx ihui ao obiy