Where to Get the Lagging Tail
The Lagging Tail is found in two places: on certain wild Pokemon and on Route 47. The easiest way to get a Lagging Tail is to find one on Route 47. When you reach the bridge at the end of the route, choose to go south instead of north; the Lagging Tail is inside a Pokeball at the end of the route. In addition, both Slowpoke and Lickitung have a 5 percent chance of holding a Lagging Tail when they are captured.
How to Use the Lagging Tail
To make a Pokemon hold a Lagging Tail, select "Pokemon" from the bottom screen of your Nintendo DS to access a list of your current group of Pokemon. After selecting the Pokemon to hold the item, select "Item" followed by "Give." Select the Lagging Tail from the list provided. If you want to take the item from a Pokemon later, select "Take" rather than "Give." When a Pokemon holds the Lagging Tail, that Pokemon takes its turn in battle last. At first glance, this might seem like a worthless item. However, the Lagging Tail can be used both offensively and defensively when combined with the right moves.
Lagging Tail Offensive Uses
The offensive power of Lagging Tail is utilized in moves that require a Pokemon to move last. For example, "Metal Burst" only works when the Pokemon who is using it has been attacked last. When your Pokemon is holding the Lagging Tail, you can ensure it will always be attacked first, since it moves last. Similar moves include "Avalanche," Counter," "Payback" and "Revenge." With these moves, you attack with twice the power of the attack that hit your Pokemon. Ideally, equip Lagging Tail on a Pokemon with a large amount of health, so that he can withstand a powerful attack, most likely defeating the Pokemon who used that attack on the same turn.
Lagging Tail Defensive Uses
The Lagging Tail has only one real defensive use; any Pokemon that knows the move "Trick" can take advantage of the Lagging Tail. When "Trick" is used, the Pokemon who used it swaps its held item with its opponents, meaning your opponent's Pokemon is now forced to go last each turn as it is now holding the Lagging Tail. This combination can be especially useful against Pokemon with a high speed statistics, such as any Psychic-type Pokemon. The Move Tutor in the Battle Front, located at the Battle Frontier, can teach Pokemon the move "Trick" for 48 Battle Points.