I'd be a little cautious about spending so much resources on a larvitar - except if it were 100%.
Why not wait and see if you will need it - if Mewtwo drops soon, it may be that so many trainers will show up that groups of 20 will suffice with less then optimal mons... And if legendaries end you can try to collect more Ttars.
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Which Bite/Crunch Tyranitar to create?
I currently have one 98% B/SE tyranitar (which I'm happy to keep as is) and I'm sitting on 145 t-tar candy.
The best raid t-tar I have is 87% IV with a 14 attack stat. I have enough charge TMs to (hopefully) make its fire blast into a crunch.
I also have a 14/14/14 larvitar which I could evolve, use TMs on if need be, and power up to level 30 with rare candies (I have 200 or so of those).
Which one should I mess with, if either?
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Your advice isn't ideal for everyone, but I'm going to consider a dark level 31 Houndoom, level 29 Scizor, level 30 Dragonites. Those instead of scrambling to make another level 20 raid Tyranitar viable. A lot of chatting raiders in my city, plus I already have several useable Tyranitars. Makes sense for me to save what rare candy and stardust I can gather for a Mewtwo or whatever else they present.
