This is my initial attempt at building a viable deck based around Curiosity, and to a slightly lesser extent, Guttersnipe.
The way I tend to play is a bit more towards slow and methodical, so almost the entire deck is built around playing defensively and maintaining control while pinging every turn.
There are two things of note about this deck:
1. This deck has "no" cards with a CMC over 3. This is partly to help Guttersnipe start doing damage as soon as possible after hitting the field, and partly so that it can function on a relatively small mana base.
2. This deck is meant not to worry too much about removing opposing creatures, as they generally won't be able to prevent the damage dealt by this deck anyway. At any rate, there is plenty of that in the Side Deck.
Offense:
Invisible Stalker - Essentially unpreventable damage. Nearly perfect synergy with Curiosity.
Guttersnipe - Good target for Curiosity. The main reason why I have so many 1- and 2-CMC instants and sorceries in the deck.
Defense:
Slumbering Dragon - Sure, it can't do anything (except tap) until after five attacks have been declared. However, this creature is great for deterring attackers, especially when the opponent realizes that they only get four attacks until it wakes up.
Lobber Crew - With four toughness, this Defender is safe from most of the widely-used burn spells. In a pinch, works well as a Curiosity target. Good synergy with Izzet Charm.
UNDER CONSIDERATION:
Extra Draw Power: (mainly to combo with Guttersnipe)
Faithless Looting - Low cost but zero card advantage.
Desperate Ravings - Good cost with +1 card advantage, but the random discard can be tricky. Bonus points for being instant speed.
Fleeting Distraction
Inaction Injunction
- While nice, Detain is less useful in this deck.
Tandem Lookout - Curiosity in creature form.
Mercurial Chemister
Desolate Lighthouse
Sturmgeist - For a deck based around drawing cards like crazy, this guy seemed like a good fit.
Defense/Control:
Dispel - Great for peace of mind on my turn, and an amusing counter to Syncopate.
Negate - I may replace the Syncopates in my deck with these, as generally, I will be less pressured to counter creatures.
Ludevic's Test Subject
- Mainly useful as a mana sink / removal magnet; nice to have as a possible win condition.
Fog Bank - A good defender, but Slumbering Dragon already does a good job on that front.
Cyclonic Rift - Generic, if temporary, removal.
Chemister's Trick
- To pump up Slumbering Dragon.
Ghostly Flicker - Cloudshift on steroids.
Curse of the Pierced Heart - For situations where attacking is unfavorable (or impossible).
Elgaud Shieldmate - Hexproof is nice, and she brings enough to share!
Offense/Damage:
Searing Spear - Really, the only reason this isn't 4-of in Main is because of space limitations, and that
Pillar of Flame
is just a little bit cheaper.
Vexing Devils - I'd probably try and cram 4 in, but I don't have any at present.
Delver of Secrets
- Hurt a little by the sub-optimal 17 instants & sorceries.
Runechanter's Pike - Basically, see Delver of Secrets.
Curse of Bloodletting - Powerful, but slow.
Thunderous Wrath - Excellent if Miracle'd, acceptable discard otherwise.
Dual Casting
- Gives Guttersnipe, Slumbering Dragon, and defenders a bit more utility.
Lightning Prowess
- See Dual Casting, above.
Chandra, the Firebrand - She fits nicely into the Burn/Stall theme, but it's a shame that she isn't a valid target for Curiosity.
Mizzium Mortars - Good creature removal, expensive boardwipe. Unfortunately, both abilities are less relevant in this deck.