I'm am 95% sure that skipping to end of map and killing boss in less than a minute will not get u banned.
Leaderboards are not recording a ton of things at all
(completeion times, sticky bombs used, etc)
And based on the past, i have not personally been banned for completing missions in less than a minute when it is not showing on leader boards / or the mission is not recorded at all.
Also i been doing this since b4 leader boards went down, and the simple fact that they could not tell the difference between ur time, and some one else's time because of the goddess grace bug it is really impossible for them to single any 1 out as a hacker cause any one's time could be a time from using a goddess grace (p), which could be used even if u r not with other people.
( In the past i told every one this was going to happen so it didn't really matter what your completion times were cause they were going to reset it, and people laughed and went on their way. Well it finally happened, i'm surprised it took their lazy azz's so long to do it)
PS. I am pretty sure unless they figure out how to fix the GG bug leader board is not coming back up relating to completion times.
As for why sticky bombs are not being recorded, i guess that is because of the Ahglan mission and you could spam those a ton for free, and it would not be very reliable on separating hacker from average player spamming sticky's on Ahglan for break offs.
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Kudos to them for compounding the game play stuff into accumulated instead of items obtained and used per day, this will effect botters a lot (i personally do not bot since i cant get one working on my pc)