If you want a very high Agility stat to avoid enemy attacks more often, there's a very simple way to do it. First, head to an open space - in Brannoch, Melrode and the path along Melrode Monastery work nicely - and start rotating the control stick so that Brian will continuously run in circles. While you're rotating unplug the N64 controller you're using. If done correctly, Brian should still be running in circles. The more you run, the more Agility you gain. With this method you can leave the console on and gain a nice amount of agility without any work.