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i have no idea how to use gernades, ive read old rule book and it says that say when assaulting, assaulting and defending units attack at same time? could some one please explain to me how to use gernades and where it it possible to use them. it would help GREATLY
They are used automaticly. They arent throw or used with dice or any of that. They simply provide the Unit with an ability.
Read the Codex under the Wargear section carefully. The description says what they do, and when they take effect.