i should have mentioned this will be for battle spot as well
Go to the calculator and run some calcs yourself. Plug in a few prime hits from things you would want it to wall and see how it holds up.
The weather in gen 5 (unlimited weather) made things like Excadrill very good. This is also the case with Manaphy which had 1 rest turn in rain. Pokemon like Politoed, Tyranitar and Kingdra were high ranked in viability rankings and things like Stoutland, who are now unranked, were A rank (Stoutland A- I believe) so weather wars made a whole different ranking and other pokemon useful who are nowadays pretty bad
I would take away from the special defense. Priority is more likely to impact Gren. Running some quick calcs, running Hasty costs you about 5% against stronger priority users (Weavile, Scizor, Mega Pinsir). That 5% assumes the priority hit is neutral btw, because Protean could leave you in quite a few different places typing-wise.
evs: 252 HP / 224 SpD / 32 Spe nature: Careful
Since you mentioned Heatran I'll assume this is OU. And, if you want to get rid of Heatran, why not just run Earthquake? Heatran is neutral to Ancientpower and its 60 power is pitiful. Mixzard X is not a bad idea but Ancientpower is not very good IMO. Rock Slide or Earthquake are better, depending on what you want to check.
What are the 32 speed evs used to outspeed?
I like Poison Jab -- hits grass types too, which is nice.
As far as I could calculate, max speed base 61's and below (Tyranitar, Sylveon, Magnezone, Swampert, Lapras, Pangoro, to name a few), neutral natured 252 base 72's and below (Slurpuff, Tyrantrum, Mega Tyranitar, Bisharp, Metagross, Breloom) and non-invested base 103's and below (which doesn't happen sadly).
The problem with Mixed Charizard X is that there's effectively nothing with defenses so lopsided that it beats out the Dragon Dance set besides things you're not likely to see like Avalugg and Mega Aggron.
I'd keep it but I wouldn't use it until ORAS comes out and you can give it Earth Power
It depends on your teambuilding skills and meta knowledge. Some people can make good teams in 20 minutes and others take several days to chose the pokemon via hit and trial. You can only know the effectiveness of a team by using it... a lot. It depends on all the factors you listed, imo the most important is how it matches against the metagame, especially S & A rank mons.
Got rid of it :(
1.) depends on your skill level. Don't worry about it.
The set that has been popularized by Crashinboombang is offensive SD mega scizor. On mobile now so I can't link, but check his sample team in the OU Player of the week 3 thread for the set, it is incredibly powerful and hard to stop after some boosts.
Scizor @ Scizorite
What does running a jolly nature out speed? I usually run adamant with ~136 speed to outspeed standard rotom-w and heatran.
