>>54810753Competitively, my prefence is:
Terastalization > Dynamax > Mega-Evolution >>> Z-Moves
Tera really blew open teambuilding and strategizing and tactical gameplay and decision-making in a way the others do not.
Dynamax is second because it also is usable by anyone at any time without having to sacrifice for it in a way that makes you use it on one particular mon every time, and brings the same amount of power as any other to whatever mon you choose to expend it on. It also increases the pace of the game and forces progress in a way not dissimilar to UMVC3 X-Factor. Looking at the Dynamax logo and thinking of its 3-turn usage, you can easily imagine that X-Factor inspired it in-part.
Mega-Evolution did not change many mons' gameplay in a significant or interesting way. Most became bigger beatsticks than they were before with no mechanical differences, and little reason to not mega-evolve immediately. Contrast everyone with Mega-Sabeleye from a base Prankster---there is an obvious tradeoff in capability going both ways, which makes the choice of holding off on mega-evolving a lot more practical, despite it gaining a superb ability and greatly improved defenses. In practice, most megas were braindead, on top of being artificially restricted to many fewer mons and thus predictable.
Z-Moves are in theory unpredictable, on top of being greatly punishing, and require commitment of a whole item slot despite being single-use. To call it a poorly executed gimmick is in my opinion understatement. I never liked playing with it or against it, except for certain boosted status moves. It's Dynamax but worse in every way.