Lets Make a Game Together

Meh it looks alright, besides, Poison-types are already horribly on the offensive. And it looks like its going to be signature.

smite throws a Positive at Cofag

Slow Armour
This pokemon takes 0.5 damage from moves with more than priority 0, but takes 1.3 damage from moves under priority 0.

Takes 0.5 damage from:
+7   Pursuit*
+3   Fake Out
+2   ExtremeSpeed, Feint
+1   Aqua Jet, Bide, Bullet Punch, Ice Shard, Mach Punch, Quick Attack, Shadow Sneak, Sucker Punch, Vacuum Wave

Takes 1.3 damage from:
-1   Vital Throw
-3   Focus Punch
-4   Avalanche, Revenge
-5   Counter
-6   Circle Throw, Dragon Tail

As chaos said making it only positive changes makes it less op.

Looks good.
But seriously everyone GIVE THE MON A TM LIST!!!

Jolteon
Tier: S
Pros:
High Speed
Vanguard and Sprint
Great Attack
High Base Power Attack (Thunderbolt)
Cons:
Defense is lowest stat
Stopped by Ground-types, Lightningrod, Volt Absorb and Motor Drive

It can counter Gyarados and many other Water and Flying-types. Can't counter Quagsire family though. Great in 1v1 battles with Guardian Charm.

Ground-types are the bane of its existance. It also hates Electric-immune Pokemon such as Zebstrika and other Jolteons with Volt Absorb.

Omnipotent (Ability)
Tier: Uber
Pros:
Serves as Mold Breaker, Mountaineer, Instinct, and Life Force
Allows user to deal neutral or better damage to all types
Cons:
None

Vanguard (Ability)
Tier: S
Pros:
Boosts power of Pokemons attack if Pokemon goes first on their turn
Cons:
You may forget to use the Pokemon with this ability first, or may not be able to.

Raichu
Tier: Mediocre
Pros:
Powerful base attack
Good Speed
Average Attack
Cons:
Bad Defense
Not good abilities
Checked by all Ground types and Electric-type immune Pokemon

It is well-fighting on the first turn, but other than that, it is just not a good Pokemon overall.

Chandelure
Tier: Great
Pros:
Flash Fire to be immune to Fire type attacks
Flame Boost to help Fire-type based teams annihilate the opponents
Very high SpAtk
Fire Spin is very useful when fighting large areas
Resistance to many tye
Cons:
Low HP and Speed
Fire Spins' bad accuracy