I would take a weapon with thunder atribute as its weak to that( i used devil slicer)  and take alot of shock traps and materials for more. Also if you trap it you get much better rewards so bring at least two tranqus.

No offense, but I don't think it's possible to kill a Tigrex under 20 mins, without endgame gear. Just avoid it like the quest intends. You'll kill one sooner than you think.

well sometimes you have to get lucky with him, cause i totally cant find an opening when he goes into rage mode = time lost,

most of the time, its not that ure unable to tackle the monster, its more of a time limitation problem.

for tat tigrex. ure not suppose to kill him, avoid him like the quest is meant to be done.

even by killing a low HR quest tigrex which isnt intended, ure not going to be able to get a set of tigrex armor.

some key items are only found with higher HR rank tigrex.

killing HR 3 tigrex in MHF2 will not get u the full set of tigrex armor.

i donno about MHFU

i love pit trap though, lets u get more hits off the darn tigrex. or u can abuse the bug in the first snowy mountain map and use a gun and try to get lucky XD