leveling up the following companions (for example) increase only the stat bonus, but not the skill frequency http://terrabattle.wikia.com/wiki/Eternity_Hourglass http://terrabattle.wikia.com/wiki/Luckster http://terrabattle.wikia.com/wiki/Ribbit'bit is it useful to spend 2+ million exp on them for only a minor stat bonus? typically i would use them on Z characters, so they already have hundreds on every stat
They're absolutely not a priority. Go for companions like Grand Rune, Ragnarok and Silver Bow first then, eventually, use some of your Metal Minions and OII companions (worth 75k EXP each, gained mainly via Luck Chests) to level up those with an Equip skill. Stat bonuses can be quite helpful on high level stages, but as long as you consider 2 million EXP "a lot" there's no need for you to worry (they actually are a lot, but your point of view will change when you reach the "true" end game and find yourself with nothing to do) In case you find yourself using companions like the Eternity Hourglass a lot, you might consider to invest a Metal Minion ΛΛ or two on them, just to get a big part of that minor bonus that, in some very rare occasions might come in handy (happened to me to survive to some hits with a very low HP, or to kill an enemy I was struggling with landing a hit on the last turn available, usually on stages that put restrictions on what kind of characters can be used).
