lf l have,say,a human and a orc make a half orc,and that half orc mates with a elf,would it be a half orc,a half elf,some new fusion race,or not possable? what about if i breed the half orc with another half orc? Would it be a full orc,a full human,or a half orc? lf l had one half orc breed with a human,would the child be a half orc,if so,how many generations would it take of breeding with humans to make the bloodline human?

Once a half-orc or half-elf or half-anything mates with a pure race... no matter how many generations go by... they always have a fraction of that race in them.

How this translates into game mechanics is up to each DM... maybe after several generations they no longer get certain features. It would depend on what then PC and DM agree on for each situation.

You could possibly create some sort of "half breed" race that can pick and choose a few abilities from each of its races? Keeping it all balanced, of course.

When I built my campaign world, I decided to make this whole question much easier on myself.  In Drakamar, a child of mixed parentage will have one set of the other of genetic background predominating.  This means that not only do I not  use half-elves in my world, I don't have to worry about endlessly revising racial heritage for different genealogies.  So, if a player wants one human and one elven parent, they will simply pick either set of traits and features for any question of game mechanics.  Details of appearance such as slightly pointed ears of slighter build are entirely up to them.  

I don't know what's in the new source about this if anything, but at this time, can an Orc have a child with an Elf?

If not, then I would have only they Human parts transferrable, making the child a Half-elf.

If a Human and a Half-elf creates only a Half-elf, then a Half-orc and a Half-elf would be one or the other. If a Human and a Half-elf can result in a Human, then a Half-orc and a Half-elf could also possibly end up with a Human.

If I understand what people are saying about the new source and they're correct about what they're saying about the new source, it should be possible to create offspring with mixtures of any origin pairs with origin traits chosen from both parents. Though if all those prerequisites mentioned prior apply, the immediate parentage may have no bearing on the offspring at all. One could RP hidden bloodlines (or just go all skillmonkey and to blazes with RPing origins).

Regardless how a player may wish it to work, it'll be up to the DM to determine how it works in the setting provided.

There are not official stats for things that are not half human. By all means with DM approval you can homebrew something though.

We made a Dwelf race for a half elf half dwarf. Its not public homebrew, but I copied it below so you can see what we did:

What I would probably do: 

Quote from DnDNewper >>

lf l have,say,a human and a orc make a half orc,and that half orc mates with a elf,would it be a half orc,a half elf,some new fusion race,or not possable? 

So the result is 1/2 Elf, 1/4 Orc, and 1/4 Human. I would lean towards Half-Elf as the base Race for most traits especially if raised in a Human or Elf home. I would tweak it based upon where the PC grew up. For example, if he/she were raised by Orcs, that's going to make a difference in languages, etc. Even though I would go with Half-Elf as the basis, I would probably go with +1 Charisma (not +2) since the character is such a mutt. To this I would probably add +1 Dex since the character is still 1/2 Elf (+2 Dex).So +1 Dex, +1 Char?

Quote from DnDNewper >>

what about if i breed the half orc with another half orc? Would it be a full orc,a full human,or a half orc? 

 If I'm reading this right, 1/2 Orc breeding with a 1/2 Orc would result in a......1/2 Orc.  Or do you mean breeding your mutt above with another Half Orc? The result would be 1/4 Elf, 3/8 Human, 3/8 Orc. That's pretty close to 1/3 of each of those three races. I'm probably making that mess a Human, with the +1 stats for all.

Quote from DnDNewper >>

lf l had one half orc breed with a human,would the child be a half orc,if so,how many generations would it take of breeding with humans to make the bloodline human?

 So you end up with 3/4 Human and 1/4 Orc is all. I would go with making the character Human, with the standard +1 stats for all. If you are going with the alternate pick two at +1, I would probably force one of them to be +1 Strength (standard 1/2 Orc gets +2) and leaving the other up to the player. One last thing to consider. If this 3/4 Human and 1/4 Orc character was raised by Orcs, I would instead make him/her a 1/2 Orc as a base for most traits, but with the stats I've already outlined since he/she's 3/4 Human. More generations mated with Human? Even one more generation I would consider him/her full human since the breed is now only 1/8th Orc. If still raised by Orcs? Then give him/her the Orc traits, but stick with Human for everything else like stats. And yet more generations? Human, Human, Human.

I tend to think that because there are Half-Elves and Half-Orcs (and I believe there is even a half-Dwarf although I don't recall the name for the race) that there is something about the human DNA that makes it dominant is a biological sense.  So the continued breeding of humans into a family causes the offspring to trend human.  Now an interesting thing I have brought into my world building is there are communities of Half-Orcs that choose to be tight communities, and likewise for Half-Elves.  The continued breeding of Half-Elves to other Half Elves tends to bring about the better characteristics of each of the races and the same is for Half-Orcs.  The Half Elves tend to become more graceful and yet more adaptable (+2 Chr and +2 Dex) and the Half-Orcs tend to become stronger and wiser (+2 Str, +1 Wis, +1 Int -or- +2 Str & +2 Wis).  In one variation I had the Half-Orcs modeled after the Plains Indians, and in another variation I had a tight knit community of Half-Elves modeled after a Samurai culture.

Quote from MusicScout >>

I tend to think that because there are Half-Elves and Half-Orcs (and I believe there is even a half-Dwarf although I don't recall the name for the race) that there is something about the human DNA that makes it dominant is a biological sense.  So the continued breeding of humans into a family causes the offspring to trend human.  Now an interesting thing I have brought into my world building is there are communities of Half-Orcs that choose to be tight communities, and likewise for Half-Elves.  The continued breeding of Half-Elves to other Half Elves tends to bring about the better characteristics of each of the races and the same is for Half-Orcs.  The Half Elves tend to become more graceful and yet more adaptable (+2 Chr and +2 Dex) and the Half-Orcs tend to become stronger and wiser (+2 Str, +1 Wis, +1 Int -or- +2 Str & +2 Wis).  In one variation I had the Half-Orcs modeled after the Plains Indians, and in another variation I had a tight knit community of Half-Elves modeled after a Samurai culture.

 Half-dwarves are called muls. They’re from Dark Sun. My friend played a mul fighter who was a gladiator in the free city of Tyr.

One DM I watch stated that, in his settings to keep things simple, half-species sterility in the half-offspring. He stated that it allows romance between
any origin but avoids the whole 1/4 this + 1/16 that + 3/12 the other +...

I think it would be half human, quarter orc, and quarter elf. Wouldn't be playable.

Well, I would treat this as human with some Orc and some Elf visuals, but a human for the sake of the rules.  Of course and GM can go wherever they want with it.

Maybe human in strength and ability, but bigger and slightly stronger than normal humans, along with having pointy ears in the case of a 1/4 elf, 1/4 orc, 1/2 human.

Quote from RangerTwoBlades >>

Maybe human in strength and ability, but bigger and slightly stronger than normal humans, along with having pointy ears in the case of a 1/4 elf, 1/4 orc, 1/2 human.

Maybe a human variant with a plus 2 to str and dex,instead of plus 1 to everything? (Also darkvision)

Quote from DnDNewper >>

Quote from RangerTwoBlades >>

Maybe human in strength and ability, but bigger and slightly stronger than normal humans, along with having pointy ears in the case of a 1/4 elf, 1/4 orc, 1/2 human.

Maybe a human variant with a plus 2 to str and dex,instead of plus 1 to everything? (Also darkvision)

 Definitely

Yeah, that sounds right. And maybe a +1 to constitution? Both elves and orcs have long lifespans when not killed in battle.

Or +2 to Int and Str, +1 to Dex and Con? They might actually have rules for this when Tasha’s comes out.

that sounds about right.

And, half-breed's being sterile sounds likely, because they are born of to very different races......... Kinda like with Star Wars species, they COULD technically have children, but something would be in some way....... Almost deficient?