I defeated the Wall of Flesh yesterday and decided to quit right after, when I logged in today, very powerful monsters were spawing because of the Hardmode... and they completely dominated me. So this is kinda of an advice, don't be prepared for the Wall of Flesh... but for what comes after it, I died 5-6 times to defeat some demon altars and died 20-25 times before I got my first Cobalt item, and this took me alot of time. I killed the Wall of Flesh on my second attempt, so in my opinion the Wall of Flesh is not that hard compared to all the monsters in Hardmode. My best tactic in Hardmode is, rush into the corruption and break that demon altars with the pwnhammer, bring some pots to heal when you're low, but the chance of surviving is fairly little because when you break an altar, several monsters will spawn, which deal 55-70 damage each time, after breaking some of the altars try to escape if you're still alive :P. As I said they deal 55-70 damage each attack, even when I was wearing the complete set of Molten armor, and this is the best armor in non-Hardmode. I advice to get a Phaseblade, and upgrade this to a Phasesaber. This weapon works pretty well when you're just in Hardmode. Then try to get the cobalt drill, get mythril to get the mythril drill, and finally the Adamantite Drill. Then go for the armor, if you still don't have the amount of bars for it. When you are getting the adamantite drill, you probably be able to get the full Cobalt armor. But the drills are the primary goal. Now I got a complete Cobalt armor set and getting my adamantite drill, I can only say that the fun increased twice as much now when I'm playing on Hardmode! So don't be afraid and face the Wall of Flesh! ;D

- Hyradd