if you are hesitant about spending real cash, you can buy it from someone else from steam trade.
Good way to have weapon level 5 fast if you don't care being a burden with other party members assuming you don't have appropriate loadout. (3 star stuff and doing tier 3)
Warmaster Rocket Hammer is just another sword if that's you're asking?

1. Sadly, no
2. The stages can be reasonably difficult, I had serious trouble the first couple times through. It's best to play the low-tier ones first, just so you can get a feel for the new enemy types. If you want some help, let me know ;)
3. Yes.

I feel obligated to add that the Rocket Hammer is by far one of the most useful weapons I own. It does pure elemental damage, and its knockback is simply beautiful. It's my favorite zombie smasher. The lunge is difficult to get the hang of, and if you're not used to it, it can get you in serious trouble, but this is more than offset by the DPS.

The bomb, even post-nerf, is a wonderful jelly blender.

The mask is wonderful if you're a gunner. Even if you aren't, it guards against fire and shock, which are the worst damage types IMO

I would honestly say that Crimson Hammer Tier 3 is harder than Firestorm Citadel. In FSC you're more likely to die from walking into the fire than the actual mobs themselves, and that's assuming you walk into the fire in the first place.

Rocket Hammer is great.

I personally enjoyed Crimson Hammer, and it costs about as much as a decent meal, except it's permanently applied to your entire account instead of a one-time use or something.

1. No :[
2. The stages themselves aren't so bad, but the new enemies are pretty annoying to deal with. If you can get someone with a shivermist, that helps immensely to deal with the recons and mortafires. You want a Polaris or something since you'll be dealing with rocket turrets spawning behind chest-high walls where things like brandishes can't reach them, as well. In T3, the boss is kinda cheap and I feel like there's too much stuff thrown at you at once. The battle is also subject to lag. It's nothing that can't be bypassed with an energy revive or two. You'll be really noticing it if one or two of your teammates are dragging you down.
3. Yes.

GIVE ALL THE MONEY TO BASED GABEN!!!111!!

Joking aside, both ways are fine. As for your questions:

1- No
2- Yes, dealing with pesky gremlin twackers that 1hit you with their cheap spin attack are harder than slags that sit there for 50 minutes just to try to swipe you. And that's the least of the unpleasant surprises. Ironically, it's less rewarding than FSC.
3- Yes, funny thing is that you wield the hammer the same way as a sword, instead like gremlins do with their hammers. Which i find silly, since you can't just reach the rocket's trigger with just one hand.

...they get close to you, do that smug laugh, and throws you across the other side of the room while saps you half a health bar out of nowhere! And before you ask, anyone could be too busy mauling another gremlin to even react.

Well, if you're doing it for the reward.

Isn't it called Dark Retribution?

I keep getting those DRs mixed up. I shall henceforth refer to it as Swirly Shadowy Sciency 'Sploder.

Ive done 38k damage in tier 3 lockdown with that hammer...

Now its up to you.

The questions you have asked has been already answered.
There are a few mercenaries out there who take you through tier 1 to 3 for a decent cost. Though you have a guaranteed win.

Comparing to FSC, The monsters are gremlins so its fairly difficult ... more than FSC. But the boss on the other hand is a piece of... well you know, cheap.
Its waay easier than vanaduke. He goes around putting bombs that do 2 bar dmg or less than half a bar with snarby set. And he dies easy... NOT like vana lol.

I'd say, since 6$ isint much for ya, go fer it.

Imagine if they charged $6 for every new mission.

DDR: most epic bomb ever
kill foes with your epic moves

the 2* and 3* versions are Dark Reprisal and Dark Reprisal mk II
and all of them are [crappy] against gremlins
I thought for a second that it would actually be good: Gremlin dodging AI says nope.avi
But yeah, they maul Giant Lichen Colonies, the Giant Jelly who shall not be named for fear of invoking Batabii's wrath, and Polyps. Not to mention they're good for mining purposes.

Also, certain skilled players will loan you their services for the entire t3 version if you pay them a fee. You would need to ask in /2 to find out who those people are, but I have seen knights advertising this for about 100+ CE.

"I thought for a second that it would actually be good: Gremlin dodging AI says nope.avi"

Wait, the Dark Reprisal/Retribution balls are actually considered projectiles?

I was under this impression as well, but turns out you can actually mutilate gremlins with these things if you just use them right.
-For menders, the best strategy is to run ahead of them and herd them back into the bomb's killzone while always laying new ones. When they raise their shields, overlap bombs so that the shield gets broken in half a second, often killing the gremlin as soon as the shield goes down.
-For thwackers, you have to kind of get a feel for it. Bait an attack while inside the bomb's radius and dodge it. Very often, the thwacker will now be exactly in killzone, turned against you and therefore exposed. This works less well in danger rooms where they have copious amounts of health.
-Scorchers are slow, big and often immobile. Ideal targets for DR!
-Mortafires are just jerks. Bring Callahan, a sword, or Shivermist.
-I haven't tried the bomb against stalkers as I haven't had any need to waste mist on OCH for a long time.

Generally, though, DBB is better against them as long as its able to knock them over. (Which isn't always.)

All versions of Operation Crimson Hammer are unlocked once you buy it. You can do them in any order.

You smell funny.