Peashooter

Each Peashooter stores six gene pairs, A–F, with two alleles per pair. A pair is treated as dominant if at least one allele is uppercase; it is recessive only when both alleles are lowercase.

Newly planted Peashooters are always purebred: each pair starts as double-dominant or double-recessive, never as a natural heterozygote.

Each gene pair starts with a 50/50 dominant-versus-recessive weight. After one trait appears, that same trait's next weight drops by 10 percentage points and the opposite trait's weight rises by 10 percentage points; all six pairs track this pity independently.

Genes are shown during crossbreeding. The current build also lets the player choose a preferred gene display mode in settings.

Gene A controls pea type: AA fires normal peas for 20 damage; aa fires ice peas for 20 damage plus slow; Aa fires fire peas for 30 base damage with splash and clears slow or freeze from the target.

Gene B controls size: BB and bb are normal-sized; Bb fires large peas. Large peas double damage relative to the normal-pea baseline and expand collision radius to about √2×, making large normal, large ice, and large fire peas deal 40, 40, and 60 damage.

Gene D controls lane coverage: DD and dd fire only in Peashooter's own lane; Dd fires into the current lane plus the adjacent upper and lower lanes. Edge lanes skip nonexistent neighbors. Adjacent-lane peas spawn from the Peashooter and drift toward the target lane instead of appearing as direct copies. In particular, Dd Pea-nut Shooter side shots follow Δy(t)=s·(2t−0.01t(t−1)), where s=+1 is the lower side shot and s=−1 is the upper side shot.

Gene F controls attack interval and wings: FF and Ff Peashooters usually fire one volley every [272, 300] cs, while ff Peashooters usually fire one volley every [136, 150] cs. ff displays wings; two winged Peashooters still produce wings, and winged Peashooters can float on water.

Genes C and E jointly decide whether repeat fire can happen. Repeat fire is possible when both pairs contain a dominant allele, or when both pairs contain no dominant allele; one dominant-side pair and one recessive-side pair disables it.

Repeat-capable genotypes include CCEE, CCEe, CcEE, CcEe, and ccee. Non-repeat genotypes include ccEe, ccEE, CCee, and Ccee.

After each shot, repeat chance is (40 − 10 × n)%, where n is the number of repeats already made by the current shot plus the total repeats made by the previous shot. In practice, a long burst makes the next burst harder to start; at n = 4, it cannot continue.

According to the wiki, genes C and D share a chromosome and use the same side of the inheritance draw; they should not be modeled as independent draws.

In ordinary crossbreeding, the first selected Peashooter acts as the donor and disappears. The second selected Peashooter remains on the board, keeps its current state, and receives the new gene combination.

Either left-click or right-click can start crossbreeding selection. The second Peashooter must be clicked with the same button; the opposite button cancels the current selection.

The new combination is equivalent to keeping one random allele from the target pair and receiving one random allele from the donor pair. Because C/D are linked, they use the same random side together. If the draw does not change a pair, that pair's visible behavior does not change either.

The target keeps its remaining HP, hypnotized state, slow/freeze state, and similar runtime state. In other words, crossbreeding rewrites the surviving Peashooter's genes and appearance instead of creating a brand-new plant.

A Peashooter can no longer self-crossbreed. During Time Stop, crossbreedable or plantable Peashooters still flash normally.

Special crossbreeding lets Peashooter combine with Wall-nut into a Pea-nut Shooter. Wall-nut does not visibly flash like normal Peashooters, but the rule still exists and awards the related achievement.

Since 0.17j, ice/fire Peashooters respond to Sands of Time state changes by switching between aa ice and Aa fire. Normal AA Peashooters are not part of this switch.

A Lower Waterfall add-on challenge sets Peashooter's HP to 0: it does not die immediately on entry, but any touch kills it. This is a mode rule and does not replace the normal encyclopedia HP value.

Peashooter has 48 visible variants: A gives three head colors, while B, D, F, and the C/E repeat-fire state each add two visible states.

Head color reads A: original color is normal, blue is ice, and red is fire. Crossing a normal purebred with an ice purebred reliably makes a red fire Peashooter, which is the basic story hint.

Stem thickness reads B: a thick stem means large peas. Rear leaf density reads D: denser leaves mean three-lane firing. Eyebrows read C/E: eyebrows mean repeat fire is possible. Wings read F: wings mean the fast ff type.

Hurriclover mentions outside research on pea genetics and explains the C/E dominance match behind repeat fire. The six traits turn the reference to Mendel’s pea experiments into playable rules.

The pond duel with Gatling Pea places crossbreeding inside a single-plant challenge involving movement, sun, durability, and genes.