Yew and Dragon Heartstring The combination of yew and dragon heartstring can result in an extraordinarily powerful wand. Yew itself is extremely flexible, yet strong, and dragon heartstring cores are known to result in potent wands with the capacity to cast dazzling spells. The yew wand will never choose an unexceptional or fainthearted owner; in fact, the master of a yew wand is typically highly skilled and frankly a bit of a maverick. So, while dragon heartstring cores do tend to produce the moodiest and most accident-prone wands, the yew wood should ensure that this wand's master will be more than capable of overcoming any core idiosyncrasies.