I'm confused by what you mean here.
QUOTE
Combined Runes
Many runes can be created from melding together two different elemental runes. The runes act as either or - for example, a lava rune can act as either a fire rune, OR, an earth rune - not both.
For example, lets take an imaginary magic spell that takes 4 earth, 3 air, and 1 mind. You can perform the skill with 4 dust rune and 3 air runes, and the mind rune. You can perform the skill with 3 dust runes and 4 earth runes, and the mind rune. Or, you can use 7 dust runes and 1 mind rune.
Combined runes don't modify the number of runes required for a spell, but improve the versatility of spells you can cast with one stock of runes.
As for runecrafting them, you must bring a number of runes of the first elemental type, and an equal number of essence, to the altar of the second elemental type, with that appropriate talisman (does not matter which is which). Also, to guarantee complete crafting of the desired rune, you MUST wear an enchanted emerald necklace of binding.
To highlight an example, I could either take 20 earth runes, 20 essence, and a fire talisman, to the fire altar, to create 20 lava runes. Or, I could take 20 fire runes, 20 essence, and an earth talisman, to the earth altar, to create 20 lava runes. Note that you must *use* the talisman on the altar, not just click on the altar, to create combination runes.
On a final note, talismans are consumed in the process of creating these combination runes.
That's the RC guide about combo runes - what do you mean by 'opposite talisman'?