The Bearger will eat anything in range, including monster meat. This will cause all spiders in the area to then aggro on the boss. Get a boss following you, take it toward some spiders, then arrange the timing so that as the boss does it's attack it engulfs spiders in the area effect.

The same 'timing' works for getting spiders to aggro on the bosses.

It helps to 'time' your own passage over tentacles, in conjunction with your distance from the Boss, so that you get the Boss to do its attack animation right on top of a tentacle or group of them, otherwise they'll often walk right past before the tentacle has time to rise from the ground and actually hit them. (An added bonus is that you'll have quite a few tentacle spikes and tentacle spots just lying around to pick up afterward.) Simply stand back and watch, then once they've killed the tentacles get their attention againa and continue leading them in/through the swamp to fight more tentacles until they're dead. One you have them in the swamp, often they'll stumble on their own close enough to tentacles for the tentacles to attack them, at which point they'll switch their aggro to the tentacles. The Deerclops will aggro on anyone who gets within range. Simply get close enough to him to get his aggro, then lead him away into the swamp. The Bearger will aggro on anyone carrying honey or a honey product, like taffy or pumpkin cookies, etc. All you have to do is keep them in the area. Under that definition they're all fairly 'easy', because every one of them with the exception of the Dragonfly can be led to a swamp, where tentacles and spiders will do the bulk of the work of killing them. I'd define 'easiest' as 'requiring the least effort or risk'.

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