The Codex Card Laboratory thread on the old site (started by Scarbo) was fun so I thought I'd get it started over here (If it already has been started I'm sorry but I couldn't find it).
So post any ideas you have for random Codex cards, whole new specs, or whole new colors if you want.
Here's a bunch of defensive cards because every one loves playing D in Codex.
Morningstar Farmer ($2, Tech I - Strength)
Unit - Citizen Farmer
Upkeep: If this unit patrolled last turn gain $1
Talent Scout ($3, Tech I - Ninjutsu)
Unit - Ninja Monk
Upkeep: If this unit patrolled last turn summon a 1/1 ninja token
Whoooa!! this girl can throw a shuriken at 104mph, you're in!
Red Tape ($2, Tech II - Law)
Your opponent gains x less gold during their upkeep phase
x = administrators in play -1 (up to a maximum of 3)
Sentinel Treant ($2, Tech I - Growth)
Unit - Tree
If you have 2 other tree cards or units with Can't Attack in play Forest Protector losses Can't attack and gains Frenzy 1
Giving Treant ($5, Tech II - Growth)
Unit - Tree
Upkeep: this card gains two -1/-1 runes. Then place a +1/+1 rune on two different units and/or heroes.
Once there was a big tree...
Call to Arms ($3, Balance)
Spell - Buff
All units with Can't Attack gain +2 atk/+2 armor and lose Can't Attack for this turn. Another unit or hero gains +2 atk/+2 armor this turn
All creatures must do their part