Taking and holding a Pokemon GO gym is vital to boosting your power - so here's some tips to do it better
Gyms in Pokemon GO are much more than a simple way to show bragging rights: they are a source of in-game money to purchase items such as lures, incense, incubators, or lucky eggs.
First of all - don’t necessarily be put off attacking a gym where the holding team is much higher than you. In particular, any gyms below level 5 should be easy pickings, as you get 6 Pokemon to use.
You have two options: as you choose to attack, you will be given a suggested list of Pokemon to attack with, based jointly on your available fully-healed Pokemon and also the types of Pokemon that defend the gym.
We have found it doesn’t always make most sense in practice, even if it does in theory, so you should look to swap Pokemon in and out as you see fit.
Once you have cleared the gym, and are able to claim it - resist the temptation to put your best Pokemon in. You should put a decent Pokemon in, but one that can be beaten easily by your best one. Some people go the whole hog and use Magikarp, and make it super easy.
The next step is to spend a bit of time fighting your own low level Pokemon. With each victory, you will accumulate gym XP. The aim is to get the gym to at least level 8, and fill it with a variety of Pokemon that span the various styles and damage types - making it much harder for an attacker to come up with a suitable set of Pokemon that can clear the gym.
In an ideal world, you will have some friends with you from the same team that can drop in the highest Pokemon they have once the gym is levelled up a bit, to ensure you don’t get ninjad.
Obviously, do not forget to go into your shop screen and claim a defender bonus as soon as you win, as well as remembering to check in every 21 hours if you still hold it for when the timer resets.