If you feel that the game is too easy, try out the hard mode. Visit settings and make it visible if you don't see it yet (by default, it's shown only for those who played for a while). In Hard Mode, almost all monsters' stats are higher, so it will be challenging for sure. Certain bad things will also happen more often (like injuries) and be more annoying (like malfunction) in Hard Mode. Certain bonuses, like bionics and weapon upgrades, will appear on the map less often when you play in this mode. Plus, you can get achievements and do missions only in Hard Mode.
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