2020-04-17 : For spells with {X} in their mana costs, use the value chosen for X to determine the spell’s converted mana cost. If a permanent or card in any other zone has {X} in its mana cost, X is considered to be 0.

2020-04-17 : If Lavabrink Venturer somehow has no choice made for its ability, its last ability grants it no protection abilities.

2020-04-17 : The converted mana cost of a token that isn’t a copy of another object is 0. A token that is a copy of another object has the same converted mana cost as that object.

2020-04-17 : You choose odd or even for Lavabrink Venturer before it enters the battlefield. There’s no point at which players can target it before it has gained the appropriate protection abilities.