Hi guys new player here, please be patient with me! Been playing for a week and already managed to down the heroic pheonix this event due to a lucky Nadia roll I got a while back. Really love the game so far!
Recently manged to train up my first few 5 stars and noticed that my usual method of training by spinning the x10 gold summon and feeding them to my heroes might not be the most cost effective method of training due to the steep cost of hero fusion at the 5 star level, which will very easily outstrip the cost of the x10 roll itself. Unfortunately once my team reached around late 4 star, 1 star or even 2 star units essentially became useless even as fusion fodder.
Would be cool if there was a building that allowed you to fuse together units to get a random higher rarity unit like the weapon forge (weapon forge itself seems pretty useless when you first get it it seems). This building could even only give you monsters and require like five 3 star units to fuse a 4 star but would still be incredibly useful for producing fodder for rerolls and fusion.
But I digress, my question here is what is the most gold/gem efficient method of training 5 star or late 4 star units?
My current thoughts are saving up 3 or 4 star units from gold and gem summons and fusing them five at a time, but that might be quite slow. I did get several pheonix hatchlings from the current event and they are awesome, but I want to save those for the final 5 star training stage where costs are the most expensive.
What are your thoughts on this?