Gudul Lurker is a surprisingly powerful card, so that one will stay.

I'll try Hangarback Walker instead of Frost Walker ( Walker for Walker, would you look at that!) and see how it goes.

I'm not having any problems with card draw and am a bit unwilling to take out my Claustrophobia and Clash of Wills, as they are my only interrupts.

For the sake of argument, what would you remove for Artificer's Epiphany?

I have to concur on Hangarback Walker, it's a great value card.Tap at end of opponents turn and start yours with him +1/+1 biggerer! If your dead set on including Artificer's Epiphany I would drop 2 Island's Your running mono blue and colorless.. With a top curve of 4cmc. 25 is a beefy land base! And maybe drop one or two Ornithopter since your goal is to make thopters anyway. Plus the ones you make have a 1 toughness as opposed to 0. But if your draw is good, I would drop those cards to keep the Frost Walker that's a good 2 drop. IMHO.

I've done testing with the Hangarback Walker substituted for Frost Walker and it has not gone well.

Some decks I play against run Warden of the First Tree and Fleecemane Lion. One even runs both!!

Hangarback Walker can block twice against those, but can't trade. It also loses any potential to boost if it is dead.

I haven't been convinced to add Artificer's Epiphany.

The number of lands I currently have work. It's not always about CMC curve. In this case it's about the probability of having land in your hand at the early stages of play. 25 is right for that.

For the same sort of reason all the Ornithopters need to stay. Thopters are made in the mid to late range of the game but you also need early threats. The combo of Ornithopter and Ensoul Artifact is too good to forego. Then there is a Turn 2 chance for Ornithopter plus Ghostfire Blade.

Thanks for the ideas. They have given me a chance to think about why I have made the current construction and to test other possibilities.

I am currently mucking around with Sigil of Valor and Foundry of the Consuls.

Currently playtesting with two copies of Rogue's Passage instead of two Island.

This deck is starting to have a bit of a combined Thopter and Unblockable flavour.

Tomb of the Spirit Dragon is pretty sweet against aggro decks, especially considering how common mono red is after origins.

You can look at some of the thopter decks at Pro Tour Origins to get some ideas. Hangarback Walker was definitely a star at that tournament btw.

Yeah, everyone keeps trying to get me to put Hangarback Walker in. It might work in other Thopter decks but here Frost Walker is too good, particularly if you can attach Ghostfire Blade to it, and Gudul Lurker is an undervalued card. Unblockable damage can win a match.

I need more than just to be told that a card has done well in other decks. I need to be convinced that it will suit THIS deck.

I would be loathe to put one more colourless land in this deck. After testing, Rogue's Passage is proving to be excellent. That, combined with the ability of Whirler Rogue and Gudul Lurker, sometimes means I have ten or more unblockable damage on my last attack.

Ensoul Artifact on Darksteel Citadel and my other Blue non-creature spells are shutting down aggro fairly effectively.

Thanks for your comments. Once again they are getting me to consider why this build is working.

I've been Playtesting against Stephen Berrios' Blue-Red Ensoul Artifact Top 8 Pro Tour deck and this deck is a match for that one.

Here's a deck list if you want to see for yourself.

Main

4x Chief of the Foundry
4x Darksteel Citadel
4x Ensoul Artifact
4x Ghostfire Blade
4x Hangarback Walker
3x Island
1x Mana Confluence
3x Mountain
4x Ornithopter
3x Phyrexian Revoker
3x Pia and Kiran Nalaar
4x Shivan Reef
4x Shrapnel Blast
4x Springleaf Drum
1x Swiftwater Cliffs
4x Temple of Epiphany
4x Thopter Engineer
2x Whirler Rogue

Side

3x Disdainful Stroke
2x Negate
2x Profaner of the Dead
3x Thopter Spy Network
2x Tomb of the Spirit Dragon
3x Wild Slash

You are welcome, i realy like blue and even more artifacts, the olny thing i would include is Bonded Construct to meke it even more aggro.

Good deck.

I made a mistake earlier too, I just realised. You can't attach Ghostfire Blade to Frost Walker.

Poor old Frosty "no friends" Walker.

First off great deck +1. I really love how budget it is and built it the moment I saw it with one change. I brought in 4x Harbinger of the Tides instead of the 3x Frost Walker and 1x Island as I did notice you tend to get flooded and many times you want to top deck something it is just another islands. I would suggest the harbringer after practicing as it is really effective and playing it early can sometimes give you so much tempo you just win.

If you wanted to add 4x Flooded Strand or Polluted Delta for some Islands it will keep the opening hand land guarantee but thin the deck out for later. I know this double the decks prive put it does help.

Yeah it's funny you should say that Finnithy because I was considering a different 2 drop.

It was between Quickling, Sidisi's Faithful and Harbinger of the Tides BUT, if you've done all my Playtesting for me, Harbinger it shall be!! :D

I do hear what you're saying about the lands. That may come down to preference/play styles as I've never been flooded. I also like the extra lands to get Rogue's Passage working ASAP.

I have already ruled out Sigil of Valor in favour of Rogue’s Gloves and don't wish to put an Aura instead of anything else I have. Interesting ideas, though.

Thanks all for the feedback and the encouragement.

Hmmmm. After further playtesting I'm gonna keep Frost Walker in the mix.

One example of why it works: I just played a game where I had a 5/5 Thopter out doing stacks of damage, when they played Anafenza, the Foremost.

I was able to shut Anafenza down with Claustrophobia, but they killed my Thopter with Murderous Cut.

With Frosty out I was able to finish the game with a final hit of damage. I also had a potential trade for Anafenza.

When I used Harbinger of the Tides against the same deck it was able to send a creature back to hand once, but not able to dispatch it.