Vern, the Ancient

At the beginning of your upkeep, put an age
counter on Vern, the Ancient.
If the number of age counters on Vern, the
Ancient is greater than your party size, Vern, the Ancient gains hexproof and "At the beginning of
your upkeep, gain X life, where X is your party
size".
"You see, that's the benefit of being old.
Ooold. Sooo ooold."