All Pokemon gain about 100 BST after Mega Evolving.
Pokemon: Regular BST / Mega BST / Gained
- Venusaur: 525 / 625 / 100
- Charizard: 534 / 634 (both) / 100
- Blastoise: 530 / 630 / 100
- Alakazam: 490 / 590 / 100
- Pinsir: 500 / 600 / 100
- Kangaskhan: 490 /590 / 100
- Mega Gyarados: 540 / 640 / 100
- Aerodactyl: 515 / 615 / 100
- Mewtwo: 680 / 780 (both) / 100
- Ampharos: 510 / 610 / 100
- Scizor: 500 / 600 / 100
- Heracross: 500 / 600 / 100
- Houndoom: 500 / 600 / 100
- Tyranitar: 600 / 700 / 100
- Blaziken: 530 / 630 / 100
- Gardevoir: 518 / 618 / 100
- Mawile: 380 / 480 / 100
- Aggron: 530 / 630 / 100
- Manectric: 475 / 575/ 100
- Banette: 455 / 555 / 100
- Absol: 465 / 565 / 100
- Garchomp: 600 / 700 / 100
- Lucario: 525 / 625 / 100
- Abomasnow: 494 / 594 / 100
Basically, the highest in BST is Mega Mewtwo, after that its Mega Tyranitar and Mega Garchomp. Technically Mawile gets the biggest boost to an individual stat with her ability of Huge Power going from 85 Attack to 210 attack.
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