The look of Wirewood is defined by its tall, thin, light-barked birch trees. The backgrounds of many green Onslaught block cards show their trunks lined up shoulder to shoulder.
In the storyline, the Phyrexian invasion forced elves and many other races to flee their homelands across Dominaria. Crowds of refugee elves fled to Wirewood, a place teeming with life but also harboring its own unique dangers.
Wirewood's refugee elves improvised weaponry and armor from the creatures and plants they found there, and developed magic to survive the dangers of their new home.
Over time, the magic emanating from the Mirari (throughout the Onslaught Block) gradually warped and changed the elves, turning them both more beastly and more plantlike until they became mutant monsters of the forest.