AttackRisky Attack
Flip a coin. If tails, this attack does no damage to the Defending Pokémon and Giovanni's Machoke does 100 damage to itself.

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 Machoke is 42/132, in position 42 of 132 on this checklist. Before it is 41 Erika's Ivysaur, and after it is 43 Giovanni's Meowth. The listed rarity is Uncommon.
Giovanni's Machoke is a Stage 1 Fighting Pokémon with 80 HP. The card lists level 36. In the Pokédex this is Machoke (#067), generation 1 (Kanto). The card says it evolves from Giovanni's Machop. In this catalog that name is Machop (#066). The card lists Machamp, Machamp (#068) under evolves to.
Ken Sugimori illustrated this card. The same name is on 1,112 other cards in the catalog.
Machoke (#067) has 22 other cards in the catalog. Those other cards are in 21 sets. The other printings with a release date run from 1999 to 2023. The earliest other card is Machoke 34/102 in Base (1999). That card is named Machoke, while this one is Giovanni's Machoke. Both list 80 HP. Both list the rarity Uncommon. Retreat cost there is 3, and here it is 2. 11 other cards of Machoke list a different HP.
The attack Risky Attack lists 60 damage. The cost is Fighting. Flip a coin. If tails, this attack does no damage to the Defending Pokémon and Giovanni's Machoke does 100 damage to itself. Headlock is another attack lists 20+ damage. The cost is Fighting, Fighting, Colorless. Flip a coin. If heads, this attack does 20 damage plus 20 more damage and the Defending Pokémon is now Paralyzed. If tails, this attack does 20 damage. Weakness is Psychic ×2. Retreat cost is 2.
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. Machoke can fill a slot in Generation 1 binder (Kanto). Themed lists that include this exact card are Trainer's Pokémon, Kanto Gym Leaders and their Pokémon, and Giovanni and his Pokémon. I still need this card.
Flip a coin. If tails, this attack does no damage to the Defending Pokémon and Giovanni's Machoke does 100 damage to itself.
Flip a coin. If heads, this attack does 20 damage plus 20 more damage and the Defending Pokémon is now Paralyzed. If tails, this attack does 20 damage.
Gym Challenge, in the Gym series. It was released on October 16, 2000. The printed size is 132.
42/132. It is entry 42 of 132 in this checklist.
Ken Sugimori. The catalog lists 1,112 other cards with that illustrator.
Uncommon.
Machoke #067, generation 1 (Kanto).
Risky Attack (60) and Headlock (20+).