Increase two ability scores by 1 each.

Ophidians are monstrous serpents with slender or toned or hefty anthropomorphic-humanoid like torsos and arms. Their size is Large.

Positives.

• Gain 2 additional Hit Points per level including the 1st.
• Increase carry capacity by 1 size up.
• One handed weapons without the "versatile" trait are treated as light weapons for the purpose of qualifying for two weapon fighting.
• Two-handed melee weapons can be wielded in one hand.

Negatives.

• -1 to Armor Class.
• Can't use weapons with following properties: Light, Hidden & Undersized.
• It should be harder for a Large creature to find cover (PHB p. 196). The DM will adjudicate this, but roughly speaking where a Medium creature would find total cover, a Large creature might only receive three-quarters cover; where a Medium creature finds three-quarters cover, a Large creature might only receive half cover; and where a Medium creature finds half cover, a Large creature might find none.

The blood of the Yuan-ti flows within this creature just like many of its relatives. 

• Immunity to the Poisoned Condition & Poison Damage.
• Blindsight within 120 feet.
• Creature Keyword: Monstrosity. You can be affected by a game effect if it works on either of your creature types.
• Can speak to snakes through the draconic language; They're able to understand and respond to the Ophidian back in kind. This creature can only speak Draconic.

These creatures are naturally sneaky yet perceptive. Due to their 'slimmer' bodies and their multiple head they gain the following:

• They're proficient is the following skills: Stealth & Perception.
• Advantage on Wisdom (Perception) checks.

The creature ends up biting into foes is a rapid fang fluffy, into those who are sadly in the way. This natural weapon attacks seem to rely on how many heads the actually have, as this seems rather effective, too effective.

As a action you can make a attack to a target within 10ft of you. This natural attack on a hit deals 2d6 Piercing damage + charisma modifier.
When the damage increases on the Fluffy Fangs, the Yuan-ti Ophidian, grows a extra head. As each new head adds 1d6 damage accordingly. These additional heads are grown at the levels listed below & increase the amount of damage dice by 1 accordingly.

• 3th Level = 3d6 + charisma modifier.
• 5th Level = 4d6 + charisma modifier.
• 9th Level = 5d6 + charisma modifier.
• 13th Level = 6d6 + charisma modifier.

Can use your powerful serpentine lower half to constrict the life out of your enemies that you can reach within 5ft.

You have advantage on all your grappling checks.

You use telepathy up to 120ft, the creature must know a language to understand you & you can communicate up to a total equal to your charisma modifier at one one given time.
You can speak: Draconic