Chupacabra stats, nice...
There is a Ranger Beast Master character as one of the PC choices. The pet included does not follow the PH regarding AC, attack rolls, and damage rolls, as the proficiency bonus was not added to those. In short - it should be better. I thought that was humorous.
Check the math before you play, people.
So it seems this adventure includes a Vampire player race. I have tried to reverse engineer the race assuming Standard Array Stats.
Wis +2
Cha +2 (Could also be either Int or Con, but the power of personality vampires traditionally command seems to make this make more sense)
Con +1 (Could also be Cha or Int, but given the hardiness of traditional vampires, this makes more sense to me).
Darkvision 60 ft.
Resistance to necrotic damage
Bloodthirst - drain blood from willing creature or target that is grappled, incapacitated, or restrained; melee attack (1d6 + Str necrotic damage); target's hit point maximum reduced by necrotic damage dealt until after a long rest
My Reasoning: Seems to be modified by strength. The example vampire's strength modifier is +0. So the attack could deal just 1d6 damage, or 1d6 + Str. I'm willing to bet the latter.
Feast of Blood - when you drain blood with Bloodthirst, your speed increases by 10 feet and gain advantage on Strength and Dexterity checks and saving throws for 1 minute
Languages: Common and Vampire
Ah, I forgot about that. Still, they went off the rails a little bit if that was the basis for the PC presented in the adventure. If they were using Standard Array, they definitely give Wis +2, but have a floating +1 to make one of the 13s a 14, and a floating +2 to make one of the 12s a 14. Additionally, they don't include the 1 piercing damage in the bloodthirst attack, and have added the feast of blood ability. They also removed the ability of a vampire to create a null.
Interesting that they have it up for free: testing how many people want it?