Wolfenstein Youngblood has many different Trophies / Achievements that you can unlock, one of which is the Bomber. This requires you to kill 50 foes with Grenades and explosives. It also nets you a Bronze Trophy.
Grenades first become available during Chapter 2, Riverside. It is straight forward to use in fact the game tells you how to. Simply aim with R1 (PS4) and let go to release and throw the explosive. Kill 50 foes to unlock this one!
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