Actually xmodgames is a marketplace which provides you different types of games in just one place but most of its games are paid ones, but if you want to play good quality game free of cost so it is better to go with some other similar apps available on internet like for example game hacker apk or xmodgames apk etc.
You can find many different types of apps which provides you the facility to download full version games for free, so go ahead with any option which is best suitable for your device specifications and try to search more about that particular app before downloading any modded version of it because if something goes wrong during installation process then you have no way except re-installing your operating system again without getting back all data files including installed apps as well as contacts, messages etc.
So be careful while installing anything on your phone because there are many scam websites available on internet which claims to provide you the paid apps free of cost but instead they install malicious software or virus on your mobile phone and steal your personal data like contacts, messages etc.