Deity Wars was clearly churned out by a Japanese company for a quick buck. Animations are poorly scaled to fit on Android screen resolutions (but looks fine on the more predictable resolution of apple stuff), crashing isn't uncommon, and it takes about ten minutes for even a slow person to figure out that the free game is very eager for you to shell out piles of money to buy boosts.
Beneath that, however, is a surprisingly compelling game, as long as you aren't a hermit.
At heart it's a clone of Rage of Bahamut, another game published by the same company but from a different developer. You build a group of troops and go around gathering better troops, upgrading your troops, and fighting other players for their stuff. They present the troops as cards in an attempt to try to call it a CCG, but you never do anything cardy with them, so don't expect a mobile Magic the Gathering. Battles are straightforward; troops have an attack value, a defense value, and sometimes a special ability to influence those values for your army. In a fight, your totals are tallied, skills go off to multiply your totals, and the person with the highest number wins. Not really rocket science, which is why I mentioned not expecting MtG. You do however get to have several different decks set up for attacking and defending, so it's wise to specialize high defense and high offense.
Where the shine starts however is in the grouping system. While searching for cards and treasure you will occasionally encounter a "raid boss". These monsters are difficult to outright impossible for one person to beat, so you're given the option after fighting them to call in the beatdown squad. If you do, everyone on your friend list and everyone in your guild is given the option to go join the fight, with two hours on the clock. If the boss gets dropped in that timeframe, the loot pinata bursts and everyone who contributed gets stuff. Unlike PvP fights where the outcome is decided in one hit, raid bosses hit back after attacks, and the fight lasts for several rounds, so using a group with high offense but low defense will see them wiped out in one round before they can do much damage. Setting up a boss-specific deck with a good blend of offense and defense is not a bad idea, as PvP decks won't fare too well.
Other events thus far include a big dungeon crawl, where players with guildmates on nearby floors receive significant boosts to their speed, and currently a guild war is in effect where four guilds get thrown into the thunderdome for an hour to attack each other for special prizes. Cooperative design shines through there too; guilds split into front line members who are higher level and doing the attacking and defending and back line members who are too weak to contribute directly but apply buffs to the front line people while being immune to attack.
tl;dr - unpolished but fun if you're into pokemoney 'catch em all' and enjoy finding and upgrading units. Getting a guild or people on your friend list is fairly mandatory for the best pasts of the game.
The SA thread covering the game to greater detail is here.
The referral code to get a little pile of free starting supplies from me is sbu2255 just be sure to send me a PM or something on here so I can try to track you down in-game and add you to my friend list.