How would dual type moves even work? so if you use for sintance an electric/Water Move on a Water type, would it be neutral since electric is supereffective but water is resisted? It would just overcomplicate things if you ask me. How about taking an aproach like this. As an example I will break appart tri-attack, it will now deal 30 ice damage, 30 fire damage, and 30 electric damage, spread over 3 hits. Something like that seems more managable.
Either the first part, which is unlikely, or a move that has one type but has the effects of another type. Say a Ice move that has the effect of the Fire type.
If you'd actually read the Pokebeach leaks, they say that the parts that were most likely lies were Espurr/Meowstick and that you have two rivals, one of which gives you their starter in the postgame. Anything else is probably true.
Unfortunately, in the case of dualtype moves. I hope they don't pick an overpowered (just combine the multipliers!) or utterly pointless (it's like a move of one type that gives STAB to another type! Which really only means it's like a move of one type but the members of that type don't want it, and most other Pokemon don't even notice the alleged second type!) implementation.
LMAO at the idea that such a move would be 'utterly pointless'. In the right situation, changing the attacking type post STAB could completely redefine the right pokemon.
Bull. What's really ridiculous are the people who want the moves to be exclusive, such as Xerneas's Geomancy.
Let's hypothetically say that Geomancy had the type effectiveness as Ground (unlikely, since it's implied he's using it on a Dragonite, but let's play along), STAB of Fairy, and is Xerneas-exclusive. For sake of argument, its attack power is 80.
Now, let's say that Geomancy was 100% Ground move, Xerneas-exclusive, and its attack power is 120.
What, precisely, is the difference between these scenarios?
Answer: Nothing whatsoever. (Well, okay, there's the possibility of a Smeargle using the move, but that's niche.)
Creator of Jay's Journey (see quote!) "It's not ten years old! Therefore, it sucks!" - Nostalgia whores everywhere