They are easy to make and there aren't that many commercial ones out there that someone with imagination could make some nice TD genre or Hybrid genre games...
the reason i think that there arnt that many comercial games are because of blizzards battle.net World Editor were you can make tower defence with graphics as good as horde of orcs in fact i think i recall playin a game just like it on battle.net
and incase i confused you its Warcraft III Frozen Throne's battle.net
so if you like tower defence games thats the place to go there are crap loads of them and being someone that played prety much all of them to date the best one ever(my opinion) is Gem TD.
Note: until this post i thought TD were invented by Blizzard learn somethin new every day on this forum
I liked onslaught, desktop tower defense and vector TD, but as long as they are 2D, simple, not medieval and 'good' graphics, I enjoy them all ^^.
No progress yet with the game other than that I replaced the bloody death animation with a desintegration animation of which im not happy with yet :P .
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