Over GTS in Ultra Moon I got a Tangrowth. I figured I'd check it's stats and they were great. However, waiting until LV 40 for a Tangela to learn Ancient Power and evolve doesn't appeal to me. I've looked elsewhere, but I got vague answers at best. If it's possible, great then I can make a Tangrowth with amazing stats. If not, well, I'll still make the Tangrowth, but it'll be a bit weaker than I planned. Not a huge loss, but I'd like the stats to be as high as possible. Thank you for your input. BTW, this is the Tangrowth I plan to make: Tangrowth (Male) Function: Tank Nickname: Grassman Item: Big Root/ Assault Vest Moveset: Giga Drain Earthquake Sludge Bomb Knock Off
You can also teach it Ancient Power via the move relearner on Mount Lanakila (in the Pokemon center).
To get Heart Scales, eat at a restaurant.
Source, Heart Scales Found Here and Here.
Hope I helped!