Cumulative upkeep {W} or {U} (At the beginning of your upkeep, put an age counter on this permanent, then sacrifice it unless you pay its upkeep cost for each age counter on it.)
When this creature dies, create a 1/1 white Bird creature token with flying for each age counter on it.
Jötun Owl Keeper has 2 listed printings; the most valuable is the printing from CSP at US$0.15 on TCGplayer's market price. Prices below are the cheapest in-stock listing in the United States.
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