This app was mentioned in 6 comments, with an average of 3.00 upvotes
It's a mobile Tower Defense game that uses Metal Slug units
It also gave us Cat Ear Leona Here
I don't think there is an established name for the genre aside from calling it a tower defense or RTS. Linear real time strategy tower defense would be my best, if not concise, description of the genre. There is a Metal Slug game in that style, you should give that a try.
https://play.google.com/store/apps/details?id=com.snkplaymore.android014&hl=en_US
It's the most recent first-party MS title. A mobile freemium tower-defense-type deal that incorporates very nearly every character and enemy to've ever turned up in the series (... plus over a hundred additional waifus, I kid you not). Been in active development by SNK for years now, and expands on the lore of the original series quite a bit.
Google Play / iTunes / /r/MetalSlugAttack
Fair warning, though, freemium games are for those with either a lot of patience or a lot of money. MSA plays entirely differently to the regular Metal Slug titles - but if you want to see sprite art from the series, it has a massive library of the stuff.
I actually love the Epic War style of games, where you set up a party of units and they spawn and fight automatically for you, with none to little (maybe casting spells or setting priorities) interaction.
This makes the game less twitch action and more strategic/tactic, where setting up the right party is the meat of the game.
More examples are Metal Slug Attack and the absolutely gorgeous My Little Army.
I tried to make an idle game with this kind of combat a while ago but it didn't quite work. Feel free to try it yourself, I would love to play an Epic War with even more idling mechanics.
If the Play Store app on your phone won't show an update, then the Play Store website often lets you work around it.
https://play.google.com/store/apps/details?id=com.snkplaymore.android014