Build a base RNG Crafting Machine coin ETA — the 150K savings plan

What the calculator models

The Coin ETA & income calculator is a player-input tool that turns the unstructured “save up 150K” advice into a scriptable projection. It accepts your current coin balance, the highest wave your base clears, your Fortune Relic tier, and your active/offline hours, and returns:

• Waves remaining to the target.
• Active hours to the target under your entered cadence.
• Offline hours to the target (when eligible).
• Calendar days to the target.
• The four-column loadout comparison (F2P baseline, Coin Boost user, Coin Boost + Potion, full stack with the 2x Boss Drops! gamepass).
• The optimal boost window sequence — exact seconds to wait between activating the boost and starting the first wave.
• The park-this-balance threshold — the minimum balance you should keep in reserve after every spend.

Every constant in the model is exported from the tool’s source so the math is auditable.

The four constants every player should know

The model constants are public in the tool source (with their provenance):

Provenance labels appear verbatim in the tool’s source and propagate to every output.

The model, in plain words

Per-wave reward, the building block of the model, is:

base_coin_per_wave   = lerp(300, 500, clamp01(current_wave_cleared / 30))
effective_wave_reward = base_coin_per_wave
                      × (1 + fortune_relic_tier × 0.10)   [capped at +100%]
                      × boost_factor                       [1.0 or 2.0]
                      × potion_factor                      [1.0 or your multiplier]
                      × boss_2x_in_play_factor             [1.0 or 2.0 on boss waves]

The model then computes:

• waves_remaining = ceil(max(0, target_balance_coins - current_balance_coins) / effective_wave_reward).
• active_hours_to_target = waves_remaining × seconds_per_wave_active / 3600, divided by 1.30 if Auto Wave is unlocked.
• offline_hours_to_target = (waves_remaining × (1 - 0.85) × (1 + 0.35) / 0.20) × 60 / 3600 if eligible.
• days_to_target = ceil(remaining_coins / daily_coins) for the entered active/offline split.

The offline formula bakes in the mob-path-distance factor (0.85) and the offline difficulty penalty (0.35) the way the spec describes them. It is conservative — best used as a ceiling rather than a precise prediction.

The four-column loadout comparison

The calculator renders a side-by-side table of four loadouts (collapsing to three when solo with zero potions):

The 4th column collapses when the player has zero potions because the boost-only user and the boost+potion user produce identical numbers. The collapse is automatic — no manual toggle required.

Optimal boost window sequence

The recommended sequence is a four-step runbook designed to align 100% of the 3-minute boost window with combat:

buy_potions(min(count, ceil(active_hours_to_target / 30)))
activate_coin_boost
wait(180 - 15)         // wait 165 seconds — start first wave 15s before the boost ends
start_first_wave

The 165-second wait is the spec’s “max(0, 180 - 15)” constant: start a fresh wave 15 seconds before the boost expires so the boost lands on the first wave’s coin payout window, not on the downtime between waves.

The calculator exposes the literal sequence so you can adapt it to your cohort’s cadence.

Auto Wave vs. low waves

Auto Wave is a 10,000-coin Skill Tree node that gives +30% throughput when active. The model:

• Applies the +30% when max-auto-clear ≥ 20.
• Applies a 0.85× throughput penalty when max-auto-clear < 20 (the node underperforms at lower waves — community observation).
• Surfaces a red warning chip if the player is in that regime.

When offline income is eligible

Offline income is eligible when:

• current_wave_cleared ≥ 1, AND
• max_wave_auto_clear ≥ current_wave_cleared

In that regime the offline branch is computed per the spec’s formula. When the branch is not eligible, offline_hours_to_target returns null and the calculator surfaces a warning chip.

Edge cases the calculator handles

• Solo player with zero potions → 4th column collapses; redundant comparison is suppressed.
• max_wave_auto_clear > current + 5 → capped at current + 5; “Forward-projected max wave capped” warning.
• current_balance_coins ≥ target_balance_coins → CTA = “You are above the 150K gate — unlock Crafting Machine now.”
• current_balance_coins > 2 × target → CTA = “Long past 150K — are you spending on the right upgrades?”.
• Multiple stacked potions > 3 → capped at 3 stacked potions in the same window; the 4th rolls into the next session.
• fortune_relic_tier × 0.10 > 1.0 → capped at +100% to prevent runaway compounding.
• boss_drop_coin_bonus applied outside a boss wave → ignored; only credited when the cleared wave crosses a multiple of 20.

The honest summary

• The 150K gate is real — three independent community guides converge on the same number.
• The per-wave baseline is documented but [SINGLE-SOURCE] — allthings.how is the only publisher of the 300→500 ramp.
• Offline income is real — developer’s official copy confirms it; the penalty rate (0.35) and DPS factor (0.20) are inferred from the genre and labelled as such.
• Coin Boost and Coin Potion stack — the calculator’s loadout table makes the marginal value of each consumable visible.

Related reads

• Bosses and relics — what the 150K gate unlocks.
• Luck calculator explained — companion tool.
• Beginner guide — the Skill Tree priority that produces useful wave income.