i am looking for a game i played as a kid

a very long time ago probobly before 2015 i played an online game which had its own website.

the information i have about it is
its free
you unloked units via card packs (and as such im willing to bet it had microtransactions)
it had loads of events so after i came back after a long period of not playing the game i got a bunch of stuff
it had a wide verity of units such as undead angles or demons
these units had upgraded versions of themselfs that were rarer and stronger
i belive you played these units on a grid
the combat was probobly turn based
and it had a campaing were you would fight a series of fights of rising difficulty

if you have any information or adivce on how to find this game that would be greatly apriciated. i am well awear this is probobly inpossible to find. would there be a way to find the game based on what email i used to make the acount