My set has a cycle of 10 "enhanced" creatures (some monocolored creatures in my set have a bigger effect if mana of a specific color was used to pay their costs). Here's what I have so far:
Borderland Zealot
3W
Creature – Human Soldier (Common)
2/4
When Borderland Zealot enters the battlefield, if B was spent to cast Borderland Zealot, target creature gets -1/-1 until end of turn.
Exotic Weapon Master3W
Creature - Human Soldier (Common)
2/2
Flash
When Exotic Weapon Master enters the battlefield, if R was spent to cast Exotic Weapon Master, it gains haste until end of turn.
T: Tap target creature.
Crosswind Drake3U
Creature – Drake (Common)
3/1
Flash
Flying
When Crosswind Drake enters the battlefield, if G was spent to cast Crosswind Drake, regenerate it.
Dwarven Pioneer
3R
Creature – Dwarf Nomad (Common)
2/4
When Dwarven Pioneer enters the battlefield, if W was spent to cast Dwarven Pioneer, you may search your library for a Plains card, put it onto the battlefield tapped, then shuffle your library.
Streetwise Scoundrels3R
Creature – Human Rogue (Common)
3/1
First strike
When Streetwise Scoundrels enters the battlefield, if U was spent to play Streetwise Scoundrels, each opponent sacrifices a permanent unless he or she pays 1.