Yeah playing through on hard it was very convenient, being able to string attacks together and not get hit meant i could use it on every second or so mech and it lowers their numbers really quickly.
I found i got all the combat upgrades and only started upgrading the staff when i had done all the other 3 and was playing through again for achievements.
Didn't get focus attack unti my second play-through on hard. Actually finding it easier than normal now :)
I find that if you're attacking a group of mechs then any mechs that get a glancing blow from the focus attack will get stunned while you're taking out your primary target. Very Handy.
I just played the game on Hard & totally dismissed the focus attack thinking it would be just useful in those boss fight moment where the dog is down & you can wail on him for a few moments. As a result the most frustrating part of the game, BY FAR, was having to fight large groups of mechs.
So getting that thing is probably for the best.
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