A het is a normal-looking dragon that carries one hidden copy of a recessive gene. A possible het is a dragon that might carry it, and the percentage is the real chance that it does: 67% het when both parents were hets, 50% het when one was. A dragon becomes proven, 100% het, the moment it produces a visual baby.
Ball python keepers will recognize all of this. Dragonbred tracks the math for you, but knowing where the numbers come from is what lets you plan.
What a het is
Recessive genes need two copies to show. Albino, Striped, Piebald, Racer, Cobalt, Masked, Bone Horns, Regal and Lava all work this way. A dragon with just one copy looks completely Normal, yet passes that copy to half its eggs. That dragon is a het, short for heterozygous.
You can't see a het. Dragonbred never shows you a dragon's genotype, only its look and what the game knows about it. That knowledge appears on the card as a line like "het Albino" (certain) or "67% het Albino" (possible). If the gene works differently from recessive or the inheritance basics are new to you, start with dragon genetics 101.
Where possible het percentages come from
Every percentage on a card is a real probability, worked out from the dragon's parents. Here are the ones you will see most:
| Parents | Normal-looking babies are |
|---|---|
| Visual × normal | 100% het |
| Visual × het | 100% het |
| Het × het | 67% het |
| Het × normal | 50% het |
| 67% het × normal | 33% het |
The 50% is the easy one. A het passes its hidden copy to half its eggs, and the normal parent has nothing to add.
The 67% takes one more step. Pair two hets and the eggs split four ways: one in four gets two copies and hatches visual, two in four get one copy, and one in four gets none. The visuals are easy to spot, so set them aside. Of the three normal-looking babies left, two carry the gene. Two out of three is the "66% het" keepers have always talked about. Rounded properly it is 67%, and that is the figure Dragonbred prints.
The 33% follows from the same logic: a dragon that is 67% likely to carry the gene, passing it to half its babies, gives each of them a one-in-three chance.
Dragons from crates work the same way, except the percentages come from the crate's odds rather than known parents. A plain-looking wild import can arrive with a possible het already on its card.
Proven: how a het reaches 100%
A possible het becomes proven the instant it produces a visual baby. A visual Albino needs an Albino copy from each parent, so any normal-looking parent of an Albino must carry the gene. There is no other way that baby could exist.
After every hatch, the "What the clutch taught you" panel lists what changed for each parent. When a visual hatches, the parent's line jumps to certain and the panel stamps it PROVEN. Proving your first het also completes a starter step worth 80 Scales.
The tutorial gives you a head start here. The two carriers in its free crate are already proven het Striped, which is why their odds are a clean 25% Striped per egg.
How to prove out a possible het
Proving out is the hobby term for testing a possible het. The fastest test is to pair it with a visual. If the dragon is a het, each egg has a 50% chance of hatching visual. If it isn't, none will.
Every normal-looking baby from that pairing is a small piece of evidence against the dragon being a het, and the game updates the percentage after each clutch. Here is how a 67% het Albino's chance falls when paired with an Albino and only normal-looking babies hatch:
| Normal-looking babies so far | Chance it is het |
|---|---|
| 0 | 67% |
| 1 | 50% |
| 2 | 33% |
| 3 | 20% |
| 4 | 11% |
| 5 | 6% |
| 6 | 3% |
| 8 | <1% |
One average clutch of four takes a 67% het down to about 11%. Two clutches take it below 1%. But a single Albino at any point ends the test: the dragon is proven.
Some practical notes:
- Use a visual mate. A het mate also works, but each normal baby tells you less, so the number falls more slowly.
- A normal mate teaches nothing. Pair a possible het with a Normal and every baby looks Normal whether the gene is there or not. The percentage won't move.
- The game never says "not het." The lowest it will print is "<1%," because no run of normal babies can rule a carrier out completely.
Het or hidden: genes under Patternless
A het is different from a gene the game shows as "hidden." Hidden genes are ones covered by another gene on a higher layer. Patternless, the super form of Sparse, removes the markings, so it hides other pattern genes and any element. A Patternless dragon carrying Spotted shows "hidden Spotted" on its card, and possible hidden genes get percentages too, like "50% hidden Spotted."
The difference matters when you plan. A het needs a second copy before it can show. A hidden gene would show if the covering gene weren't there, so a baby that inherits it without Patternless shows it by that gene's usual rules.
Why proven hets matter
Proven hets are the backbone of any recessive project. With two proven hets, you know each egg is 25% visual. With two 67% hets, it drops to about 11%, because there is a real chance one or both carry nothing. Reading breeding odds shows how possible hets change the odds cards.
They are also worth more in Scales:
- Releasing a dragon pays 8 extra Scales per proven het.
- An order for a clutch from a proven het pair pays by the odds you can see, so knowing the hets lifts its price.
- On the market, a sold dragon keeps everything known about its genes, so the buyer sees the same "het Albino" you earned.
That last point is why keepers bother proving dragons they plan to sell. A proven het is a dragon the next keeper can plan around. If you are building toward a first visual, how to breed an Albino dragon walks through the whole route, and planning a breeding project covers longer lines. The fastest way to learn it, though, is to pick one possible het in Dragonbred and prove it out.
Frequently asked questions
What does 66% or 67% het mean?
The same thing: Dragonbred rounds two in three to 67%. It means the dragon has a two-in-three chance of carrying one copy of a recessive gene. It's what normal-looking babies from two het parents are, since one in three of them carries nothing.
What does 50% het mean?
The dragon has an even chance of carrying the gene. It's what normal-looking babies from one het parent and one Normal are.
How do you prove a het in Dragonbred?
Breed it and hatch a visual baby. Pairing a possible het with a visual gives each egg a 50% chance of being visual if the gene is there, which is the fastest test.
Can a dragon be confirmed not het?
No. Each normal-looking baby lowers the chance, and the game will show it falling to "<1%," but it never says a dragon is not het.
Published October 6, 2026 · updated October 22, 2026
Start with twelve founders, read the odds on every egg, and chase the morphs nobody has hatched yet. Free in your browser.
Play Dragonbred free
