Timbermare was created as a tribute to pro player Jamie Wakefield's wife Marilyn (nicknamed "Lovely Mare"), who died of ovarian cancer. Keep in mind that Magic sets are designed about a year in advance, and Planar Chaos came out about a year after her death, meaning that the card was designed almost immediately after the tragedy. The full story.
Being the creator of a multi-billion dollar game allows Richard Garfield to create some nifty cards. But there's more! The art of the first card was left undocumented by Garfield's request, which was for the longest time honored by the entire Internet (but can now be seen here◊). The second card speaks for itself, and if you don't get the art for the third, consider why the artist put four plates on the table.