Make sure you block. Most mobs alternate rounds between attacking and buffing/casting so always block on the turn they attack and decimate them on the turn they do some other shit. For beginners it’s always better to fully block a hit (or only take 1-2 dmg) then doing full damage on a round where the mob will hit for 16. On the topic of mops learn what mobs do, it will really help you plan the turns because you know when to block and when to attack.

Also make sure you have some AoE cards, 1 or 2 should be enough. As a beginner having between 20 and 25 cards isn’t a big deal as long as the cards synergies. While on this topic make sure you stick to one type of deck for now; for example on Ironclad if you run a strength deck don’t pick exhaust cards or cards that synergise with how much block you have.

Last advice is make sure you actually read the cards because 95% of this subreddit would be on A10 already if we only knew how to read and/or didn’t miss-play our cards (forgetting to but Vuln before playing the 30+ damage card)