I borrowed the concepts for these from the video games, so naturally most of them were best suited as tools (hold items).
Shell Bell
Item - Tool
Whenever the Pokémon this card is attached to does damage, remove 2 damage counters from that Pokémon.
Toxic Orb
Item - Tool
At any time, if this card is attached to your Active Pokémon, that Pokémon is now Poisoned, but can not be affected by any other Special Conditions.
Assault Vest
Item - Tool
Any damage done to the Pokémon this card is attached to is reduced by 20. Prevent all effects (excluding damage) of this Pokémon's attacks.
Life Orb
Item - Tool
The Pokémon this card is attached to does 20 more damage with each of its attacks. Whenever that Pokémon does damage, place 2 damage counters on that Pokémon.
Lagging Tail
Item
While setting up the game, after selecting an Active Pokémon, you may play this card. If you do, your opponent goes first. If both players play Lagging Tail, ignore both of them.
Safety Goggles
Item - Tool
Prevent all damage counters that would be placed on the Pokémon this card is attached to between turns.
Zoom Lens
Item
After flipping a coin for an attack, you may play this card. Flip that coin again.
Amulet Coin
Item - Tool
Whenever the Pokémon this card is attached to Knocks Out another Pokémon, you may draw a card.
Shell Bell
Item - Tool
Whenever the Pokémon this card is attached to does damage, remove 2 damage counters from that Pokémon.
Toxic Orb
Item - Tool
At any time, if this card is attached to your Active Pokémon, that Pokémon is now Poisoned, but can not be affected by any other Special Conditions.
Assault Vest
Item - Tool
Any damage done to the Pokémon this card is attached to is reduced by 20. Prevent all effects (excluding damage) of this Pokémon's attacks.
Life Orb
Item - Tool
The Pokémon this card is attached to does 20 more damage with each of its attacks. Whenever that Pokémon does damage, place 2 damage counters on that Pokémon.
Lagging Tail
Item
While setting up the game, after selecting an Active Pokémon, you may play this card. If you do, your opponent goes first. If both players play Lagging Tail, ignore both of them.
Safety Goggles
Item - Tool
Prevent all damage counters that would be placed on the Pokémon this card is attached to between turns.
Zoom Lens
Item
After flipping a coin for an attack, you may play this card. Flip that coin again.
Amulet Coin
Item - Tool
Whenever the Pokémon this card is attached to Knocks Out another Pokémon, you may draw a card.