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  5. UE12BT: Kaiju No. 8
  6. Childhood Promise

Union Arena · UE12BT: Kaiju No. 8 · #UE12BT/KJ8-1-075 · Common

Childhood Promise

Union Arena card price for Childhood Promise: $0.07 market, from $0.01 at the cheapest listing, Normal printing, updated Oct 20, 2026. Full price history since Oct 31, 2025 below.

Market price · Normal · Oct 20, 2026
$0.07
+16.7% this week · +16.7% in 30 days
Buy on eBay →
1 day0.0%
7 days+16.7%
30 days+16.7%
90 days−12.5%
1 year—
All time−50.0%

Sellers right now

$0.01lowest listing$6.50highest
Market price$0.07
Mid listing$0.10
30-day avg$0.06

Market price is what a near-mint copy actually sold for. The cheapest listing is what a seller asks today — on thin markets the two differ a lot.

Where to buy

TCGplayer$0.07

One year

$0.0652-week low$0.1452-week high
In the range13%
All-time low$0.06
All-time high$0.14
First priceOct 31, 2025
Normal · market price
$0.06$0.09$0.12$0.15
$0.07
Oct 2025Feb 2026Jun 2026Oct 2026
TCGplayer market price · via tcgcsvtcgrate.com

Price story

Childhood Promise came out in October 2025; we leave the first weeks out of this story, because early prices are set before real supply exists. Listings currently start at $0.01; over the last 30 days the market price averaged $0.06.

Printings

PrintingMarketLowHigh7d
Normal$0.07$0.01$6.50+16.7%

The card in play

Card type
Event
Series Name
Kaiju No. 8
Required Energy
2
Action Point Cost
1
Activation Energy
Green
Card text

Choose one character on your field and switch it to active. If the chosen character is "Kafka Hibino", "Kaiju No. 8", or "Mina Ashiro", choose up to one of your AP cards and switch it to active.

Trigger

[Draw] Draw a card.

Other printings of Childhood Promise

1 more · $0.07 – $0.57
All printings
Childhood Promise (UEPR/KJ8-1-075), Kaiju No. 8 Release Event Cards — Union Arena card price −3.4% 7d Childhood Promise UE12BT: Kaiju No. 8 Release Event Cards · #UEPR/KJ8-1-075 $0.57

Also in UE12BT: Kaiju No. 8

most valuable
Full set
Kikoru Shinomiya (020) (SR**) (UE12BT/KJ8-1-020), Kaiju No. 8 — Union Arena card price 0.0% 7d Kikoru Shinomiya (020) (SR**) UE12BT: Kaiju No. 8 · #UE12BT/KJ8-1-020 $188.67 Kaiju No. 8 (055) (SR**) (UE12BT/KJ8-1-055), Kaiju No. 8 — Union Arena card price 0.0% 7d Kaiju No. 8 (055) (SR**) UE12BT: Kaiju No. 8 · #UE12BT/KJ8-1-055 $181.99 Mina Ashiro (005) (SR**) (UE12BT/KJ8-1-005), Kaiju No. 8 — Union Arena card price 0.0% 7d Mina Ashiro (005) (SR**) UE12BT: Kaiju No. 8 · #UE12BT/KJ8-1-005 $155.02 Reno Ichikawa (012) (SR**) (UE12BT/KJ8-1-012), Kaiju No. 8 — Union Arena card price 0.0% 7d Reno Ichikawa (012) (SR**) UE12BT: Kaiju No. 8 · #UE12BT/KJ8-1-012 $139.16 Kafka Hibino (063) (SR**) (UE12BT/KJ8-1-063), Kaiju No. 8 — Union Arena card price +4.1% 7d Kafka Hibino (063) (SR**) UE12BT: Kaiju No. 8 · #UE12BT/KJ8-1-063 $119.20