just wait a little bit (~10 mins) and restart to fix the game. Clearing cookies and cache can also help. and if youre using chrome switch to firefox. Its not your side, its that decas servers are getting more laggy because of the sudden influx of players
@mymomsmom i have had that same problem (believe me, ive ran ~250 cems looking for resu so far) All you have to do is run away from the monster to where you couldnt see it if it was there. when you run back, it'll be there, ready to kill (please note, this is very hard to do with multiple people)
 "Realm of the Mad God"){kind=icon}
 "TextRPG: The Rise of Diablo"){kind=icon}
 "Pinata Hunter 2"){kind=icon}
 "Tangerine Tycoon"){kind=icon}
 "ELEPHANT RAVE"){kind=icon}
 "Idle Mine"){kind=icon}
 "i saw her too, with lasers"){kind=icon}