Mechanic · structure & scoring · role-playing game
Visible encounter
A battle that starts when the party touches an enemy that walks the map, rather than from a random roll.
On this page
In a visible encounter the enemies are on the map, and a battle starts when the party touches one. In EarthBound, the facings at the moment of contact decide who strikes first: an enemy caught standing or from the side gives the party the first strike, and one charging a party that faces away gets it instead1. Enemies far below the party’s levels turn and run from it2. EarthBound Beginnings still rolls random encounters per step3.
- Touch and facingEarthBound (1994). Enemies walk the map; who faces whom at contact decides the first strike, and enemies far below the party run away.1,2
Games
| Game | Year | How | Note |
|---|---|---|---|
| EarthBound | 1994 | Touch and facing | enemies walk the map; who faces whom at contact decides the first strike, and enemies far below the party run away |
Every claim about this mechanic, by game (2)
References
- ^ abIn EarthBound (US release), a battle starts when an enemy on the map touches the party, and the two's facings decide who strikes first. With the direction from the enemy to the party rounded to one of eight: the party strikes first when the enemy isn't moving toward the party (within 45°) and the leader isn't facing away from the enemy; the enemies strike first when the enemy is moving toward the party and the leader faces away; otherwise neither does. A standing enemy always gives the party the first strike.CodeHerringway/ebsrc
How we know
17 LDA TOUCHED_ENEMY ⋮ 24 ADC #.LOWORD(ENTITY_MOVING_DIRECTIONS) ⋮ 28 CMP #8 29 BNE @UNKNOWN0 30 LDY #0 31 LDX #1 32 BRA @UNKNOWN6
src/unknown/C0/C0D19B.asm lines 17–32 at 68aec5c · upstream ↗ 49 JSL UNKNOWN_C41EFF 50 LDY #$2000 51 CLC 52 ADC #$1000 53 JSL DIVISION16S_DIVISOR_POSITIVE 54 STA @VIRTUAL04 ⋮ 57 SEC 58 SBC @VIRTUAL04 59 AND #$0007 60 BEQ @UNKNOWN1 61 CMP #1 62 BEQ @UNKNOWN1 ⋮
src/unknown/C0/C0D19B.asm lines 49–99 at 68aec5c · upstream ↗ Checked against the evidence by its author, an AI model, 2026-10-21.
Checked by a second AI model, 2026-10-21.
- ^ abIn EarthBound (US release), an enemy on the map turns and runs from the party when its group's run-away event flag holds the value the group names (its run_away_flag_state byte), or when the levels of the party's main characters (not guests) summed are more than 10 times the enemy's level; more than 8 times for 3 enemies in 4, and more than 6 times for 1 in 2, by a random byte each enemy gets when it spawns.CodeHerringway/ebsrcrevised
How we know
24 OPTIMIZED_ADD battle_entry_ptr_entry::run_away_flag ⋮ 31 JSL GET_EVENT_FLAG ⋮ 36 ADC #battle_entry_ptr_entry::run_away_flag_state ⋮ 43 LDA @LOCAL00 44 CMP @VIRTUAL02 45 BNE @UNKNOWN0 46 LDA #1
src/unknown/C0/C0C524.asm lines 24–47 at 68aec5c · upstream ↗ 49 JSL UNKNOWN_C0546B ⋮ 53 ASL ⋮ 60 ADC #enemy_data::level ⋮ 65 OPTIMIZED_MULT @VIRTUAL04, 10 66 STA @VIRTUAL02 67 LDY @LOCAL00 68 TYA 69 CMP @VIRTUAL02 70 BLTEQ @UNKNOWN1 71 LDA #1 ⋮ 73@UNKNOWN1: 74 LDA @LOCAL01 ⋮
src/unknown/C0/C0C524.asm lines 49–105 at 68aec5c · upstream ↗ 2UNKNOWN_C0C615: 3 REP #PROC_FLAGS::ACCUM8 | PROC_FLAGS::INDEX8 | PROC_FLAGS::CARRY 4 JSL UNKNOWN_C0C524 5 CMP #$0000 6 BEQ @UNKNOWN0 7 JSL GET_OPPOSITE_DIRECTION_FROM_PLAYER_TO_ENTITY
src/unknown/C0/C0C615.asm lines 2–11 at 68aec5c · upstream ↗ 412 JSL RAND 413 LDX @LOCAL06 414 STA ENTITY_WEAK_ENEMY_VALUE,X
src/overworld/spawn_enemies_from_group.asm lines 412–414 at 68aec5c · upstream ↗ Checked against the evidence by its author, an AI model, 2026-10-21.
Revised after a check by a second AI model, 2026-10-21.
- ^In EarthBound Beginnings (English build), each step in an area with encounters starts a fight when a random byte is below a rate from the table 32, 21, 16, 13, 10, 8, 6, 5 (in 256), indexed by the area's frequency class (1–7) plus a counter, capped at the eighth entry. The counter rises by 1 with each encounter, up to 2, so the rate drops after fights; it returns to 0 in areas without encounters and after a fade-out transition.CodeNathan-R-Og/mother · “EarthBound Beginnings (USA, Europe) (Virtual Console)”
How we know
560DoWalkingStep: ⋮ 579 ;get areaEncounterDef based on area 580 ldx map_area 581 lda AREA_ENCOUNTER_LIST, x ⋮ 586 ;else, write 0 587 sta UNK_24
src/global/prg/title.asm lines 560–594 at e0b3e3f · upstream ↗ 615 @EncounterFrequencyExists: 616 clc ⋮ 618 ;if frequency is >= 9, cap it to 8 619 adc UNK_24 620 cmp #9 621 bcc @NoForceCap 622 lda #8 ⋮ 627 ;get a random value 628 jsr RNG_BYTE ⋮ 631 cmp AREA_FREQ_TABLE-1, x 632 ;if random value >= area_freq_table[x], leave 633 bcs @FrequencyFail ⋮
src/global/prg/title.asm lines 614–645 at e0b3e3f · upstream ↗ 694 AREA_FREQ_TABLE: 695 ;lookup table for frequencies 696 .byte 32,21,16,13,10,8,6,5
src/global/prg/title.asm lines 694–696 at e0b3e3f · upstream ↗ In the cartridge (“EarthBound Beginnings (USA, Europe) (Virtual Console)”): bank $14 $B58B, the eight rates as the ROM has them. We don't reproduce the bytes.
2761 ;fade out 2762B30_0b57: 2763 jsr BANKSET_H13 2764 jsr OverworldTransitionIntepreter ⋮ 2770 lda #0 2771 sta UNK_24
src/global/prg/constant.asm lines 2761–2771 at e0b3e3f · upstream ↗ Checked against the evidence by its author, an AI model, 2026-10-21.
Checked by a second AI model, 2026-10-21.
Sources
Code
- Herringway. 2026. “ebsrc: Source code recreation for the game Earthbound.” Commit 68aec5c. Herringway/ebsrc @ 68aec5c · licence, all uses
- Nathan-R-Og. 2026. “mother: Disassembly of Mother/Earthbound Zero/Earthbound Beginnings for the NES.” Commit e0b3e3f. Nathan-R-Og/mother @ e0b3e3f · licence, all uses
- n.d. “EarthBound Beginnings (USA, Europe) (Virtual Console).” · licence, all uses