A comprehensive guide covering hero upgrade priority in Last War Survival. It explains which heroes to level first for maximum impact, with special attention to UR hero shard allocation and free-to-play efficient strategies. Covers top picks like Kimberly and optimal upgrade order. A comprehensive guide covering hero upgrade priority in Last War Survival. It explains which heroes to level first for maximum impact, with special attention to UR hero shard allocation and free-to-play efficient strategies. Covers top picks like Kimberly and optimal upgrade order.