Pocket Creature
http://www.kongregate.com/games/NTFusion/pocket-creature
A game where you upgrade and evolve 4 base creatures.
A good setup to use from lvl 6 on forward:
Shadow dragon
Soul Seeker
Scarface
Scarface/Corpseking
After you complete the game you unlock Endless Mode.
Best setup known (left to right):
-Shadow dragon
-Shadow dragon
-Bladespirit
-Romeo-S (with blood leech effect)
This setup got me to wave 93 with 368 kills and 552,000 gold.
Upgrading the Shadow dragon boosts attack by 100, rather than 0.5 speed:
66 a3 1b 2f 10 a0 61 a3 1b
66 a0 1b 24 7f a0 61 a0 1b