Here is the full list of all 32 Mayan Death Robots achievements.
Finish the game
Unlock Pakal
Defeat Ixtab
Unlock Huracan
Win 10 games with Hunahpu
Defeat Tohil
Unlock Alom
Defeat Cabrakan
Unlock Itzamna
Defeat Kukulkan
Meet the Mayas
Kill 10 enemy Mayas in one shot
Win 10 games with Hun-Batz
Win 10 games with Alom
Win 10 games with Chac
Win 10 games with Ah-Puch
Win 10 games with Huracan
Win 10 games with Itzamna
Win 10 games with Akna
Win 10 games with Pakal
Win 10 games with Xbalanque
Kill the enemy robot 8 times in one match
Win a match in 4 turns
Find and destroy Robama in the Blizzard
Freeze 5 times in the Blizzard Event
Let a snowman finish the fight
Win a fight without pressing ready
Let the Spanish steal your core
Let the ballistae win the fight
Let the Joyride UFO finish the fight
Let a Spanish helicopter finish the fight
Kill 9001 Mayas in total