Complete all the Theatre of Blood Master tasks in a single run - tob, mechanical, theatre of blood - 71 -> Completed after I failed bloat flies task the first run (was the only one I didn't complete in the first run) but completed it on the second run, aka this one completed at bloat. So reckon this one is not working as intended.
Completed 2 zuk kills in a row, didn't get the achievement.
Remarks:
Tried the endurance 50 kc without leaving with bandos which worked, so assuming it will work with all, cba testing all of them.
Nylocas Vasilias master achievement is a bit of a useless one since there is only 1 elite achievement.
Kill JalTok-Jad without taking any damage works in practice mode inferno.
Kill Zuk wihtout killing Jad works in practice mode inferno.
Complete wave 68 of the Inferno with a Rune Crossbow works in practice mode inferno -> without message shown.
Bandos kill with staff also didn't show me a message but it did correctly complete.
This is all I got to test at the moment. I'll post a new reply if/when I find more.
EDIT:
Not all task provide the corresponding failed message, some give a message, some don't.
The cox Master and Elite task completed after I finished my last Cox task, which was in crabs room, so not even in a single full run (see image)
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Also got the nex Master achievement to complete all elite task in a single kill while failing 1 task (see image)
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Kill all 6 Barrows Brothers without taking damage from any of the brothers - 7 -> Not working in risky barrows or while doing normal barrows
Other bugs:
Can't create a slayer helm when the normal one is (i)
Asking Ghommal to make a Tztok Slayer helm gives you the Tzkal helm
Teleport on hilt to saradomin is not correct (see image)
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Also an idea, like in osrs to be able to attach ghommal's hilt 6 to the avernic defender?