Donating Spells and Siege Machines should give donater more XPs
Considering the time and cost needed to prepare a spell or siege machine to donate, I think it should give the player which donate them more XPs. For instance right now, with donating a 30 space troop(golem, lava, etc), player gets 30 xps, while donating Siege Machine which is more expensive and need more time to cook, give the player 0 XPs? This also cause the players to donate these SM or spells less than normal troops, because at the end, they are not motivated somehow(unless they are very generous, haha)!