AttackAncestral Memory
Flip a coin. If tails, this attack does nothing. Either way, you can't use this attack again as long as Giovanni's Magikarp stays in play (even putting Giovanni's Magikarp on the Bench won't let you use it again).

Gym Challenge is a set in the Gym series. It was released on October 16, 2000. The printed size is 132, and the checklist is the same length. Giovanni's Magikarp is 73/132, in position 73 of 132 on this checklist. Before it is 72 Giovanni's Machop, and after it is 74 Giovanni's Meowth. The listed rarity is Common.
Giovanni's Magikarp is a Basic Water Pokémon with 30 HP. The card lists level 9. In the Pokédex this is Magikarp (#129), generation 1 (Kanto). The card lists Gyarados, Gyarados (#130) under evolves to.
Ken Sugimori illustrated this card. The same name is on 1,112 other cards in the catalog.
Magikarp (#129) has 44 other cards in the catalog. Those other cards are in 40 sets. The other printings with a release date run from 1999 to 2026. The earliest other card is Magikarp 35/102 in Base (1999). That card is named Magikarp, while this one is Giovanni's Magikarp. Both list 30 HP. The rarity there is Uncommon, and here it is Common. Mitsuhiro Arita illustrated that card, and Ken Sugimori illustrated this one. 4 other cards of Magikarp list a different HP.
The attack Ancestral Memory lists 40 damage. The cost is Water. Flip a coin. If tails, this attack does nothing. Either way, you can't use this attack again as long as Giovanni's Magikarp stays in play (even putting Giovanni's Magikarp on the Bench won't let you use it again). Flail Around is another attack lists 10× damage. The cost is Water, Colorless. Flip 3 coins. This attack does 10 damage times the number of heads. Weakness is Lightning ×2. Retreat cost is 1.
I keep a set binder for Gym Challenge, meant to hold every card of that set. This card is one slot in the Gym Challenge set binder. A generation binder holds one card of each species. Magikarp can fill a slot in Generation 1 binder (Kanto). Themed lists that include this exact card are Trainer's Pokémon, Magikarp and Gyarados, Kanto Gym Leaders and their Pokémon, and Giovanni and his Pokémon. I still need this card.
Flip a coin. If tails, this attack does nothing. Either way, you can't use this attack again as long as Giovanni's Magikarp stays in play (even putting Giovanni's Magikarp on the Bench won't let you use it again).
Flip 3 coins. This attack does 10 damage times the number of heads.
Gym Challenge, in the Gym series. It was released on October 16, 2000. The printed size is 132.
73/132. It is entry 73 of 132 in this checklist.
Ken Sugimori. The catalog lists 1,112 other cards with that illustrator.
Common.
Magikarp #129, generation 1 (Kanto).
Ancestral Memory (40) and Flail Around (10×).