- 20 Squire Rels spawn after 6.67 seconds200f, delay 1~3 seconds30f~90f.
- 10 Relic Doges spawn after 20 seconds600f, delay 2~6 seconds60f~180f.
- 5 Shibalien Elites spawn after 33.33 seconds1,000f, delay 3~9 seconds90f~270f.
- When the base reaches 99% HP:
Strategy 1 (Cyberpunk Stacking)
Treasures: Full CotC treasures (chapters 1,2,3) so this means increased slowing time on aliens and increased damage.
Battle: Spawn a Cyberpunk Cat as quickly as possible, and use Maglev, Slapstick Cats, and Zamboney Cats to hold off the enemies. If you can somehow keep a peon without dying, then stack Cyberpunk Cats. If you're like me and are not adept at this, on base hit, spam meatshields, Macho Legs, Zamboney, Maglev Cat, and Cyberpunk. A Macho Legs at this level can tank a hit from an Elder Sloth, dispatch the Shibalien Elites with ease, and help knock the M. Ost back, though for this strategy, it is better to snipe the Shibaliens with Maglev Cat to prevent the M. Ost from pushing. Once you get 2 desynced Cyberpunk Cats hitting the M. Ost, you can use all the cats except the Slapstick Cats to keep the M. Ost at bay. Once the M. Ost has bit the dust, you'll win with no issue.
Other notes: as Wuffa remarks, Goemon Cat can be used to generate money in the beginning. Also, Manic Macho Legs might be a better option for another cheap attacker, though the focus on this strategy is to kill the R. Ost and not focus on the backline, which is what other strategies focus on.
Strategy 2 (Major Leaguer Cat)
Treasures: Chapters 1 and 2 or more.
Strategy: Use Goemon Cat to make bank with the Squire Rels. Spawn Mina and a Seafarer Cat, and Manic Macho Legs (with Seafarer Cats as a last resort) until the beginning peons are cleared. The goal is to take up as much time as possible so you don't need to wait a while for a second Mina. Once you hit the base, the goal is to spawn Major Leaguer Cats and just enough Seafarer and Macho Legs Cats to keep a Shibalien Elite to trigger Major Leaguer's attack without getting overrun by them. In this strategy, your goal is to snipe the Elder Sloths, and not to kill the M. Ost. Once this happens, you're pretty much done.
Notes: Cyberpunk Cat sure would be useful here. Lucas IV has a similar strategy using Cyberpunk Cat and Cat God the Great. There might also be a cheesing strategy using a really well-timed Slow Beam/Iron Wall cannon to keep the M. Ost pinned to the base so Cat God the Great doesn't die, but it probably isn't worth the time it takes to just do a legitimate strategy.
Strategy 3 (ft. Stone Cat)
Treasures: CotC 1 only.
Strategy: Stall at the very beginning for cash and begin to stack Slapsticks Cats along with Manic Macho Legs. Kill off the Shibalien Elites with Can Can to prevent them from overwhelming you. On base hit, starting spawning stone cat and the other meatshields once M. Ost is a decent distance away from the sloths, refrain from spamming Can Can Cat as the Shibaliens actually prevent Slapsticks from approaching the Elder Sloths, along with M. Ost's slow. Slapsticks spam should be able to take out the M. Ost with time and a little luck.