Duocasting/Tricasting/Quadcasting/Pentacasting/Hexcasting/Heptacasting/Octocasting

You can concentrate on two spells rather than one. When your concentration is broken, you choose which spell to end.

You can choose this feat multiple times. If you do, you can concentrate on an additional spell for every time you choose this feat, up to 8.

This is traditionally an Elvin technique, however, your dungeon master can remove this in a world where the knowledge is known by other races.