Whats the best tower defence or game like that on facebook or easy to load

I disagree, BTD limits absolutely NOTHING and you can play as long as you want with all content available.
kingdom rush-
limits heroes
gives privileges to ppl that pay[another skill, another reinforcement, reinforcement skins]
cant play levels above 12.
i think some upgrades are limited? o-o
prob forgot some.
BTD:
coins are only an addition, you only need the bucks and it gives you bucks for completing lvls so thats perfectly fine.
can play all levels
can play all towers
can have all upgrades.

Please understand and read my original posts.

I never said that Kingdom Rush offered more as a free user.
I stated that to get the best possible game experience kingdom rush was more value for money.

Yes compared to the amount of levels in BTD kingdom rush lacks a huge amount how ever the game works differently and random level designs that work fine in BTD would not work in Kingdom Rush. I did not state BTD is not a good fun cheap game to play as it is.. I only state the gameplay on Kingdom Rush is far richer than BTD.

I do how ever wish Kingdom Rush would release a developers pack for premium users to create custom maps.

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So what did I say in a nut shell,

Inregard to paying for the best experience both games offer kingdom rush is far better value for money with a richer gameplay that is far more in depth. How ever BTD has a huge amount of levels aswell as a large amount of additional content and its basic structure is what makes it good.

Both games are good how ever I prefer and believe Kingdom Rush is better for time spent playing. its my personal opinion that its better not a fact.

About the levels thing i think i read something that would make that possible. although it wont be really good since KR is based on a story-line unlike BTD which is just a war between the Bloons and monkies rofl.
Kr limits you number-wize when it comes to buildings, its kinda annoying but i guess its like that cus of the two Extra modes and the story line.
Kr is cawl and takes more thinking cus of the limit but its good, still taking a liking for BTD tho.

These are some great suggestions guys, you made my work life so much more bareable. Now I have another question, is there any games out there like BTD but maybe 2 player?

most tower defense games i've seen lately are for mobile phones. on iOS and android. maybe you could look a bit there and see if you'll find anything you like?