Xeon, Soul Consumers

Hexproof, Vigilance
At the beginning of your upkeep, you may choose one of the two options:
Exile target creature, and Xeon gains +1/+1.
Exile target creature, and create a 1/1 spirit token.
When Xeon dies, you may exile him. If you do,
deal {x} damage to target opponent or creature,
where X is equal to the power of Xeon.