Flying
At the beginning of each end step, if a creature died this turn, create a Food token. (It's an artifact with "{2}, {T}, Sacrifice this token: You gain 3 life.")
{2}{B}, Sacrifice another creature or artifact: Old Flitterfang gets +2/+2 until end of turn.
Old Flitterfang's triggered ability will check as the end step starts to see if a creature died this turn. If none did, the ability won't trigger at all.
8 Nov 2024
You can't sacrifice a Food to pay multiple costs. For example, you can't sacrifice a Food token to activate its own ability and also to activate Maraleaf Rider's ability.
8 Nov 2024
Whatever you do, don't eat the delicious cards.
8 Nov 2024
Food is an artifact type. Even though it appears on some creatures, it's never a creature type.