Breed the Blaziken. Bold isn't a good nature for it. And just saying, but Blaziken is an Uber, meaning it can't be used in standard play. Infernape is the closest alternative:
-Fire Blast/Flare Blitz
-Close Combat
-Grass Knot/Stone Edge/Thunder Punch
-U-turn/Mach Punch/Thunder Punch
Nature: Hasty/Naive
EVs: 168 Atk/88 SAtk/252 Spe
Item: Life Orb
If this is for Battle Spot, use this Blaziken:
-Flare Blitz
-High Jump Kick
-Swords Dance/Protect
-Stone Edge/Protect
Nature: Jolly/Adamant
EVs: 252 Atk/4 Def/252 Spe
Item: Blazikenite/Life Orb
Ability: Speed Boost
Sceptile is outclassed by other Grass Pokemon like Ferrothorn, Mega Venusaur and Amoonguss because while it's fast, it doesn't have much to set itself apart from those Grass Pokemon. These Grass Pokemon have better utility options or coverage. Who knows, things may change when Mega Sceptile is officially released:
Amoonguss:
-Spore
-Giga Drain
-Foul Play/Sludge Bomb
-Clear Smog/Sludge Bomb
Nature: Bold
EVs: 252 HP/120 Def/136 SDef or 252 HP/252 Def/4 SDef
Item: Black Sludge
Ability: Regenerator
Ferrothorn:
-Stealth Rock
-Leech Seed
-Power Whip
-Gyro Ball/Thunder Wave/Protect/Knock Off
Nature: Relaxed
EVs: 252 HP/88 Def/168 SDef
Item: Leftovers
Ability: Iron Barbs
Mega Venusaur:
-Giga Drain
-Sludge Bomb
-Leech Seed/Sleep Powder/Earthquake/Knock Off
-Synthesis
Nature: Bold/Relaxed
EVs: 252 HP/240 Def/16 Spe
Item: Venusaurite
or
-Giga Drain
-Sludge Bomb
-Hidden Power (Fire)/Earthquake/Knock Off
-Synthesis
Nature: Modest/Quiet
EVs: 240 HP/252 SAtk/20 Spe
Item: Venusaurite
Swampert was good in Gens 3 and 4, but it's not that good anymore, considering the power creep that made it difficult for it to deal with harder hitters; its lack of reliable recovery doesn't help either. Gastrodon, Quagsire or Slowbro are better alternatives. Once again, things may change when Mega Swampert is legal, but that will only be an option on rain teams:
Gastrodon:
-Scald
-Ice Beam/Earth Power/Earthquake
-Toxic
-Recover
Nature: Bold/Relaxed
EVs: 252 HP/252 Def/4 SDef
Item: Leftovers
Ability: Storm Drain
Quagsire:
-Scald
-Earthquake
-Toxic
-Recover
Nature: Relaxed
EVs: 252 HP/252 Def/4 SDef
Item: Leftovers
Ability: Unaware
Slowbro:
-Scald
-Psyshock/Fire Blast/Ice Beam
-Thunder Wave/Toxic
-Slack Off
Nature: Bold
EVs: 252 HP/232 Def/24 SDef
Item: Leftovers
Ability: Regenerator
While Boomburst is tempting on Noivern, it's not worth it because it has redundant coverage with its Dragon STAB. Only Exploud makes good use of it because it gets STAB on the move. Draco Meteor is also a more powerful Dragon STAB to use:
-Draco Meteor
-Hurricane
-Flamethrower/Focus Blast
-Taunt/Roost
Nature: Timid
EVs: 252 SAtk/4 SDef/252 Spe
Item: Life Orb
Ability: Infiltrator
Mega Kangaskhan is banned to Ubers. Diggersby is an alternative:
-Swords Dance
-Return
-Earthquake
-Quick Attack
Nature: Adamant
EVs: 4 HP/252 Atk/252 Spe
Item: Life Orb/Focus Sash
Ability: Huge Power
If this is for Battle Spot, this is the Mega Kangakshan set to use:
-Fake Out/Power-Up Punch
-Return
-Sucker Punch
-Earthquake/Crunch
Nature: Jolly/Adamant
EVs: 252 Atk/4 Def/252 Spe
Item: Kangaskhanite
Ability: Scrappy
Aegislash is an Uber, but if this is for Wi-Fi/Battle Spot, don't use SD/King's Shield, as it's easily walled and crippled. Much better sets below:
Aegislash:
-Shadow Ball
-Shadow Sneak/Iron Head
-Sacred Sword/Iron Head/Pursuit
-King's Shield
Nature: Quiet
EVs: 244 HP/12 Def/252 SAtk
Item: Leftovers/Spooky Plate/Spell Tag/Air Balloon
or
-Substitute
-Toxic
-Shadow Ball
-King's Shield
Nature: Modest
EVs: 244 HP/12 Def/252 SAtk
Item: Leftovers
or
-Shadow Ball
-Shadow Sneak
-Flash Cannon/Pursuit
-Sacred Sword
Nature: Hasty/Naive
EVs: 4 Atk/252 SAtk/252 Spe
Item: Life Orb
or
-Swords Dance
-Shadow Sneak
-Shadow Claw/Iron Head
-Sacred Sword/Head Smash
Nature: Adamant
EVs: 252 Atk/4 SDef/252 Spe
Item: Life Orb
If you follow tiers, use alternative Ghost Pokemon here:
Gengar:
-Shadow Ball
-Sludge Bomb/Sludge Wave
-Focus Blast/Thunderbolt
-Destiny Bond
Nature: Timid
EVs: 4 HP/252 SAtk/252 Spe
Item: Life Orb/Focus Sash
or
-Substitute
-Shadow Ball
-Will-o-Wisp
-Taunt/Disable/Sludge Bomb/Sludge Wave/Focus Blast
Nature: Timid
EVs: 28 HP/148 SAtk/80 SDef/252 Spe
Item: Black Sludge
Sableye:
-Taunt
-Will-o-Wisp
-Recover
-Foul Play/Knock Off
Nature: Bold/Impish
EVs: 252 HP/252 Def/4 SDef
Item: Leftovers
Ability: Prankster
Chandelure:
-Substitute
-Shadow Ball
-Fire Blast/Will-o-Wisp
-Taunt
Nature: Modest
EVs: 160 HP/156 SAtk/192 Spe
Item: Leftovers
Ability: Infiltrator
or
-Fire Blast
-Shadow Ball
-Hidden Power (Ice/Fighting)
-Trick/Energy Ball
Nature: Timid/Modest
EVs: 4 Def/252 SAtk/252 Spe
Item: Choice Scarf
Ability: Flash Fire/Infiltrator