Jigglypuff’s HP (Health Power) is 60. Pineco carries the same HP (Health Power) as Jigglypuff (60). Jigglypuff’s first attack (Hypnotic Gaze), for only the cost of 1 energy (Colorless) does no damage, but puts the defending Pokémon to sleep. Carrying on, Jigglypuff’s second attack (Expand), for the cost of 2 energy (Both Colorless), does twenty damage, with the phrasing below the attack of “During your opponent’s next turn, any damage done to Jigglypuff by attacks is reduced by 20 (after applying weakness and resistance)”.

Now moving on to Pineco. Pineco’s first and only attack does 20 damage, with no other special abilities. Because of the ability on Expand for the same cost of Pineco’s only attack. Therefor Jigglypuff is the winner.