Mammals? is the 1st stage of The Crazed Lizard. Next stage: Draconian.
Three Crazed Lizard Cats walk out between 0:53 and 0:57, and they don't leave. Each has 600,000 HP and 755 range, far beyond anything you'd own by now, and hits the whole area. They move slowly and hit fairly lightly, so on their own they're a siege, not a rush. What breaks your line is the Otta-smack-us, which arrive in pairs about once a minute from 1:00 and hit hard. The fight is a loop: hold each Otta wave with meatshields and Macho Legs, and in the gaps between waves send the one kind of unit that can actually walk up to the Lizards and hit them.
The lineup that does it
Ten units, no gacha. The four meatshields are Crazed Macho Cat, Eraser Cat, Macho Cat and Crazed Wall Cat. Keep that set: Eraser Cat is much sturdier than Wall Cat. Macho Leg Cat is your cheap early damage. Crazed Whale Cat and Dragon Cat clear the Ottas. The key units are the Titans, Crazed Mythical Titan Cat and Mythical Titan Cat. Titan units have only one knockback, so they keep walking forward through the Lizards' hits instead of being bounced back like everything else, and they're the ones that land the blows. Get Mythical Titan to Jamiera Cat (level 20+10) if you can, since it reaches the Lizards far more often. The two Titan icons look almost identical, so put them apart in your lineup. Crazed Bahamut is the emergency button.
Treasures and items
Every Empire of Cats treasure at Superior. Mysterious Force from Into the Future makes the cat cannon recharge faster, and the cannon is your emergency push when Lizards reach your base. Bring Rich Cat, because money is scarce and the start is tight without it. Bring Sniper the Cat too, though it comes with a trade-off. The Lizards do the least damage when they stand bunched as one, and Sniper spreads them out. In practice there's usually something in front of them for Sniper to hit instead, and in exchange it keeps pushing them back from your base when that matters most.
The opening: four walls and Legs
Level the Worker Cat to 2, then send Eraser Cat, the other meatshields, and Macho Leg Cats. Legs are the damage early, because they're cheap and you can't afford anything else. Keep all four meatshields coming without a break: the Mooth rush at the start is followed by the Lizards pushing from the far end. As money comes in, add Crazed Whales. When the Ottas and Mooths pile up in one heap, send Crazed Bahamut into it, with Dragons and Legs behind him. Every kill pays well, so put it all into the Worker Cat until it's maxed.
four meatshields and Legs holding the opening · plays here, from that second
The moment of truth
With the Worker Cat maxed, spam everything, use the cannon if it's ready, and go all out on the Lizards while they're bunched. This is the hardest moment of the fight, and it decides the run: if they come out of it barely hurt, there are too many to push through. Force-close and try again instead of playing it out. It costs no energy. A good force-close signal later on: the Lizards are hitting your base and your cannon isn't ready.
Bahamut into the pile, everything out · plays here, from that second
The loop: one wall between waves, Titans after
While only the Lizards are on the field, drop to a single Crazed Wall Cat as your wall. They can't get past one line on their own, and that saves your money. When the Ottas return, go back to all four meatshields and Legs, plus a Dragon and a Whale if you can afford them. When that Otta wave dies, send Crazed Mythical Titan: that's your window to hit the Lizards. When it dies, repeat. Use Bahamut only when things look really bad, because you can't have him for every wave. The loop takes a long time, about 20 minutes. When Ms. Sign shows up saying you're too slow, ignore her: she does nothing, and there's no time limit. Even when one Lizard is left, keep running the loop rather than spamming, in case another is right behind it.
a Titan walking into the Lizards between waves · plays here, from that second
The continue, and a limit
Mammals? allows continues, and this clear budgets for one. Spending 30 Cat Food is reasonable when you're close. The catch is that the boss here is three Lizards, so the base HP won't tell you how close you are. Count the Lizards instead: continue once you've killed one or two. The continue resets the field and you start from a strong position. Set a limit before you start, 30 or 60 Cat Food, and stop there.
the long grind, Ms. Sign's sign up · plays here, from that second
The wiki's plan, and other units
The wiki takes the same approach: bulky units that can land hits before they die (Jamiera Cat, Crazed Whale Cat) and anything that outranges the Lizards. Its other route skips the fight entirely: use the money from the opening Mooths to rush the base before the Lizards spawn at 0:53, and Warlock and Pierre is the Uber for that. Hacker Cat (Nerd Cat's evolved form) has 1200 range. It stands near your base, shoots the Lizards from safety, and fits in a slot Jiangshi Cat frees up, since Jiangshi survives a lethal hit and counts as two meatshields. Crazed UFO Cat, if you've cleared Flappy Cat, can take plain Mythical Titan's slot. If you've finished Into the Future Chapter 3, Awakened Bahamut can burst into the Lizards; if he gets bounced back and killed, force-close and retry. Super Galaxy Cosmo outranges them too, but never fire the normal cannon with him out, or he walks into their range. Use Slow Beam or Thunderbolt.
THE SHORT VERSIONFour meatshields and Macho Legs to hold the Otta waves, Crazed Whale and Dragon to clear them. In each gap, send the Titans: one knockback means they're the only units that reach the Lizards. Drop to one Crazed Wall while only the Lizards are out, save Bahamut for emergencies, and force-close any run where the first big push fails. Count Lizards, not base HP, before you continue.
The general approach, from the wiki's strategy notes. The guide above walks through one full clear.
Crazed Lizard Cats outrange almost everything — you need units bulky enough to land hits before dying, or ones that outrange them.
- Jamiera Cat or Crazed Whale for bulk, Cyberpunk Cat for range; Crazed Wall Cat helps immensely if you own it.
- The opening Mooths can fund a rush — destroy the base before the Lizards even spawn; Warlock and Pierre cheese it the same way.
- Super Galaxy Cosmo outranges the Lizards, but never fire the regular Cat Cannon with him out — he walks into their range; use Slow Beam or Thunderbolt.
CRAZED MACHO CAT A Wall in the guide's clear. 
ERASER CAT S Wall in the guide's clear. 
MACHO CAT D Wall in the guide's clear. 
CRAZED WALL CAT S Wall in the guide's clear. 
MACHO LEG CAT A Early damage in the guide's clear. 
CRAZED WHALE CAT A Otta killer in the guide's clear. 
DRAGON CAT B Otta killer in the guide's clear. 
CRAZED M. TITAN CAT B Hits the Lizards in the guide's clear. 
MYTHICAL TITAN CAT B Hits the Lizards in the guide's clear. 
CRAZED BAHAMUT CAT A Emergency in the guide's clear. 
WARLOCK AND PIERRE A Warlock and Pierre - great here for cheesing the stage by defeating the base before the main bosses come out; and cost is not an issue with the initial Mooths. You may need higher levels depending on which unit you have and their own range. 
CYBERPUNK CAT A It is recommended for the player to use Cat Units that have enough health to land some hits on the Crazed Lizard Cats before being killed (such as Jamiera Cat or Crazed Whale Cat) and Cat Units that can outrange the Crazed Lizards (such as Cyberpunk Cat). ⚙ Trait counters worked out from the roster — the guide's plan doesn't need them; kept for reference
Snache is Traitless. Anti-Traitless units take less damage and deal more.
HITMAN CAT A Hitman Cat: Deals massive damage to Traitless enemies 
LONE CAT AND KITTEN A 100% KB + Freeze + Resist vs Traitless. Also fits “Out-range Snache.” 
DRILLER CAT A 100% Weakens Traitless to 10% and (True) Strong vs Traitless. Also fits “Out-range Snache.” 
D'ARKTANYAN S Strong Against Traitless on a Long-Distance area attack — answers the many Traitless bosses. Also fits “Out-range Snache.” 
JAGANDO JR. A Lord of Ruin Jagando Jr.: Strong against Traitless enemies (Deals 1.5x damage, only takes 1/2 damage) Snache reaches 110 range. Units that out-range it can chip safely without taking hits.
GROSS CAT A Range 350 — fires from beyond its 110. 
MASTER URIL A Range 405 — fires from beyond its 110. LONE CAT AND KITTEN A Range 300 — fires from beyond its 110. Also fits “Counter Traitless.” DRILLER CAT A Range 460 — fires from beyond its 110. Also fits “Counter Traitless.” D'ARKTANYAN S Range 340 — fires from beyond its 110. Also fits “Counter Traitless.” 
The castle you destroy to clear the stage.