FOOTLIGHT DISTRICT RITUAL UPDATE

I killed the last zombies which started Round 8 and spawned a second Margwa, then I killed zombies as I made my way back to the spawn point. Doing the second ritual spawned one Margwa. In that round I did the magician's ritual, then booked it to the boxing ring and began the boxer's ritual. I opened the stairway behind the player spawn with the Beast and played to Round 7. I did the same method as Devious Jedi two posts above but I took them down a little differently. If you use the Pop Shocks gobblegum you can kill the Margwa with one knife hit, I already have the achievement so I can't test it but it should work all the same if you use this although its not necessary as you can do this on a fairly low round and if you save a zombie its easy to just kill the Margwa with a gun. Two Margwas will start spawning in on higher rounds when you have 4 players (and I'm sure even on solo once you hit very high rounds but can't confirm for sure) but it's much easier to just do it on the lower rounds using rituals. I think the ritual method is certainly the easiest most sure-fire way to get the achievement. You will need to be the person that kills both the Margwas, if a teammate does it it won't count. It would be easier with a friend holding a zombie at the end of a round but I managed on solo very easily. If you're playing solo or working with a friend in co-op you can just do all 4 rituals in one round, kill both the Margwas and get the achievement that way as well. So essentially you want to kill the Margwa that spawns in from the ritual, and the Margwa that spawns in that round. If you wait to do the rituals until this round, every two rituals that you preform will spawn in a Margwa.

FOOTLIGHT DISTRICT RITUAL UPDATE

One should always spawn in on round 8 and every so often after that (should be every 7/8 rounds but I'll update when more positive). To get two Margwas to spawn in a single round your best bet is to do the following:

Footlight district ritual