Magical gene / no coat effect

Intimidating

Nothing wants to be near it. Passive animals and hostile mobs alike keep outside a radius written on the allele copy — at least eight blocks, often more. Standing next to one is the quietest place in the world.

Built, and not yet seen in game

The gene, its inheritance and its founder table exist and are covered by the test suite; the translator that turns it into behaviour was written against the 26.1.2 sources and is flagged unverified in its own comments. Nothing on this page has been watched happening to a horse. What to look at, and what is most likely to be wrong, is on To be verified.

What it does

CombinationOutcome
Itm/Itmpassive and hostile mobs both pushed out of the radius
anything elsenothing

The catch

It repels everything that is not a horse, which includes your cows, your sheep and your chickens. An intimidating horse cannot be kept in a farm without emptying it. That is not a bug, and it is the reason the gene is worth thinking about rather than simply wanting.

It is not the same as holy ward

Holy ward stops hostiles spawning. This pushes out the ones that are already there. A horse with both is genuinely safe ground — nothing appears, and nothing that wandered in stays.

Health

None to the horse. The cost is entirely to the farm around it.

Gene key
horsegenetics.intimidating
Alleles
Itm intimidating, n
Inheritance
homozygous recessive
Reaches the game as
a mob_aura repel effect with a group filter
Epigenetic
radius, minimum 8 blocks
Coat effect
none, ever
Existing verb, already capped

mob_aura repel ships and is already bounded — max_targets per beat, counted off the horse’s own tickCount so a field of them does not do all its work on one tick. This gene inherits all of that and adds only the group filter.

The group filter must use entity type tags

A hardcoded list of passive and hostile mobs makes every modded creature invisible to this gene, and to the four others sharing the filter (leader of the pack, meowing, cleansing light, holy ward). Build it on tags once.

Repel was a shove, and the shove did not work — measured, 2026-09-13

The original implementation cleared the mob's target and then pushed outward: setDeltaMovement(away × 0.35), once every twenty ticks. Three unattended hours with six cows and one intimidating horse says that is not enough. The cows were placed at three blocks; across sixty-four readings the nearest sat at a median of 4.2 blocks, and 63 of the 64 were inside the eight blocks this gene promises (minimum 0.6, maximum 8.0).

The aura was firing the whole time — the first reading moved the cows from 3.0 to 5.6 within a minute, so “it never ran” is ruled out. A shove simply loses to a pathfinder: the cow's own navigation walks it straight back over the following second, because nothing ever told the cow's AI anything. You cannot out-poke a goal once a second.

It issues a path now, which is the mechanism this file had already chosen

repelFrom calls mob.getNavigation().moveTo(…) toward the far edge of the radius, so the mob's own pathfinder does the work instead of fighting it. That is exactly what followHorse does for the mirror-image case, and its comment already contains the argument: a navigation nudge rather than an injected goal, because “a goal added to an arbitrary mob has to be taken off again, and a horse that dies, despawns or stops expressing would leave it behind on every creature it had ever met”. A path expires by itself. Repel is the same problem pointed the other way and should have had the same answer from the start.

The shove is kept, at 0.2. Not as the mechanism — as the reading. It is what makes the moment look like being driven off rather than like a cow choosing to wander, and on a mob with no navigation, or one that cannot path to the spot, it is the only thing that happens at all.

The avoidance goal stays rejected. The lifecycle objection was right and this change does not weaken it.

Widened from passive-only during design

The first specification repelled passive animals only, which made it a drawback with no upside — a gene whose entire effect was emptying your farm. Extending it to hostiles gives it a reason to exist, and the overlap with holy ward turned out to be complementary rather than redundant once the two were stated precisely.

Keeping the cost

It would have been easy to make this repel only hostiles and become a straightforwardly good gene. The passive half is kept because a magical locus with a real, concrete, everyday cost is rarer in this mod than one without, and “you cannot pasture this horse with your animals” is a cost a player meets on the first day rather than in a spreadsheet.

Planned source: common/genetics/genes/IntimidatingGene.java