Colosseum Wave Guide | NO PRAYER FLICKING/OFF-TICKING | SIMPLE SOLVES 

Go to the north side of your pillar if it's safe and then rotate to south pillar when reinforcements spawn. If north side isn't safe, then run straight to south pillar and either run diagonally or back to north pillar depending on how the stack turns out when reinforcements spawn. If you do decide to run to south pillar immediately ever, make sure you know how to corner trap monsters coming from the north east. Also sometimes the mage will trap the ranger if they're both spawned on that side, in that case you can just go back to default position and pray mage and wait for reinforcements to spawn then take care of everything 1 by 1.