Glyph Grow...
	Obstinate Obsidian...

After matching a certain number of objects you'll get various different kinds of glyphs (powerups) to use. However, wait and grow them by making more matches so that their power increases - it's better to wait and use a super-powerful glyph than to use a bunch of small ones.

On higher levels you'll encounter obsidian stones that can't be cleared normally. You'll have to collect and use your glyph powerups to clear them once they start cluttering the screen.