User blog comment:Sam Wang/BTD5 - Tips For Reaching High Rounds/@comment-3153244-20120808070404/@comment-3153244-20130116091703

It's only 118 but I think I died at Round 150+. I later found out that I didn't really need that many x/4 Ninjas, but I think around 10 could suffice. You really need to keep an eye on the game and use an ability as soon as another one ends.

The cash for/from the 0/4 Snipers should obtained before the high rounds (I suppose Rounds 90-105 could be your farming rounds, but if you've managed your economy properly, you could even do it before the ZOMG comes.) You need lots of x/4 Snipers for the cash to come rolling in easily. Also, despite RoDs being good, Temples and TT's are still better options.