Tree Of Life Makes Major Changes To Locks

As of Tree of Life's most recent update, the way that the game's lock mechanics work has changed. Before, players were required to lock their towers every day. Thieves could then break in by picking the lock and render the tower useless by stealing all of its arrows.

The latest update changed this. Towers now require no locks and can be used only by you and your guild members. No items drop from your towers when they are destroyed. All towers are now "arrow-filled towers."

You can see the full set of patch notes here.